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Client Testimonials

Mark is awesome! Needed a pet sitter last minute and we came across his web page. Did a meet and greet the day before and everything went perfectly from there! We got lots of lovely pictures of our puppy which was very reassuring he was in good hands. We know who to send our pup to if needed in the future! Highly recommend :)

L. O'Laughlin. Fort Collins, CO

Mark does a fabulous job taking care of my high-maintenance princess dog. I felt very comfortable being away knowing my pup was in very good hands, taken care of, and loved on! I'd recommend Mark to any of my friends and family looking for pet sitting.

A. Eining.  Fort Collins, CO.

We left our two older dogs with Mark during a long trip, and we're thrilled with the results!  Mark not only got them playing with other dogs but also improved their behavior on walks, a change we still see at home. He kept us updated with happy photos and videos, easing our worries.  Mark's exceptional care and understanding of dogs is evident.  Highly recommend for anyone needing a trustworthy, skilled dog sitter – he's so good, our dogs might start preferring him over us! 

A. Axness. Fort Collins, CO.

Mark watched our Great Dane puppy on short notice for us. Our puppy had tons of fun playing with other dogs and having fun! Mark sent us an update so we knew how our puppy was doing as well. I would recommend Mark to anyone that's looking at doggie daycare/boarding for their dog.

B. Grimes.  Fort Collins, CO. 

Mark was professional and took great care of our rabbits. I highly recommend "On the Fly Pet Sitting."

J. HoGlin. Fort Collins, CO.

I have used Mark for dog daycare for my puppy and older dog. He has the perfect setup - the dogs can go in and out at their leisure and he has a big yard for them to play in. My work schedule is a little different every day, so I have really appreciated his availability and willingness to be so flexible on drop off and pick up times. Best of all, the pups have gotten to the point that they rush into his yard overjoyed to see him, so I know they must be happy and well taken care of.

K. Hannifan.  Fort Collins, CO. 

Mark is amazing!  Made me feel extremely comfortable about someone new coming to my house to take care of my two dogs. Made sure to do a meet and greet and get all the information necessary in case of an emergency.  He’s accommodating and trustworthy.  If you are delayed in your return home, you can absolutely trust he will make sure you don’t have to worry about your four legged babies. I will use On the Fly Pet Sitting anytime I need the assistance, and I recommend them to anyone in need of a reliable and trustworthy sitter. You will not be disappointed.

K. McTernan.  Fort Collins, CO.

Mark is a great guy who instantly made a connection with my 13 year old dog Grizzly. He took excellent care of Grizzly for the week we were away and for those of you who have older dogs you know the dirty work that can entail. Mark knows dogs: he's taken care of all ages, all types. Griz was much happier with him than in a 'big box store' commercial kennel. I highly recommend Mark's services to anyone looking for pet care!

J. Runge. Fort Collins, CO.

We contacted Mark at the last minute, as we were heading out of town and our fur baby babysitter fell thru at the last minute. Mark was accommodating, met with us within a few hours and took great care of our 1-year-old husky baby. We could tell that he truly enjoys animals and has a great setup at his house with a large backyard for playing. Thanks, Mark!

B. Charbo.  Fort Collins, CO. 

My cranky 15 year old tortie needs a daily medication and she doesn’t willingly take it. Mark took on the challenge and was able to get the meds in her to keep her healthy while I was away for a week. I was able to enjoy my vacation knowing she was in good hands. 

L. Zimmerman. Fort Collins, CO.

The rest of us got home last night and I'm just now catching up on emails. We will definitely spread the word and be repeat customers in the future. 

Thank you so much for taking such great care of all of them!

L. Javernick. Timnath, CO

We have appreciated Mark's care of our pups; his knowledge of animal behavior, and flexibility make for the perfect pet sitter!  We never worry when our pets are with him.

C. Broersma.  Fort Collins, CO.
Mac and Moe - German Wirehaired Pointers

Thank you Mark! We would be thrilled to recommend you to anyone we know who might be in need of your services. Thank you for taking such great care of our kitties!

E. Riska. Fort Collins, CO.

Thank you so much!  The dogs (all 10) are happy and healthy, and we can tell that they really liked you.  So many is a challenge at times even for us, but you handled it with aplomb.

B. Nass.  Fort Collins, CO.

Mark took great care of our two dogs. Will make use of his services again, as needed. Highly recommend.

C. Fuller. Wellington, CO

Mark and Tami took great care of my pup Stetson.  I felt very comfortable leaving my pup with them when I first went to do a meet and greet.  They were also good about giving me photo/video updates while I was away and made it very easy to work with them.  Mark was also very flexible with the drop off time (I had to shift my schedule a few times due to outside factors) and so I was able to drop off my pup earlier than we had planned originally.  Would definitely have them watch my pup again if I am away.

J. Thai. Fort Collins, CO.

Mark is always warm and calm and confident with my dog, and firm when he needs to be. Mark knows how to handle dogs. My dog is a rescue and missing some of the socialization he would have ideally gotten. When I leave him with Mark, he is not just being "warehoused" so he is safe... he is being taught how to respond appropriately to new things in an enriching environment. I highly recommend Mark to other dog owners.

K. Malers.  Fort Collins, CO.

Mark is great! I felt very comfortable and assured leaving my pup Callie with him when I had an out of town trip. I highly recommend and will definitely be using him again in the future!

E. O'Donnel.  Fort Collins, CO.

We had Mark take care of our sweet, shy, four-year-old Pug, Ellie. It was her first time with any pet sitter, and we were anxious, of course. Mark sent us daily picture texts to reassure us that she was fine. When we picked her up after three full days and two nights, she wagged her tail at us, and then followed Mark around…she evidently has him pegged as the “food guy.” She did just fine, and On The Fly will be our go-to pet sitters from here on! What a good job, and what a nice guy!

J. Buchanan.  Fort Collins, CO.

Mark did an absolutely wonderful job ensuring my kitties were taken care of while I was out of town visiting my fiancée. I would not hesitate to recommend him to any friends or use his services again!

W. Ankele.  Fort Collins, CO

We had Mark dog sit for us while we attended an out of state wedding. We were very pleased with the quality of care our dog received!  We really liked that our dog got to socialize with other dogs and play at the dog park.  It was very easy to schedule our dates with Mark and his whole operation is completely hassle free and uncomplicated.  We highly recommended him.  Our dog loved hanging out with Mark and we will be using him for all of our future dog sitting needs!

Dunn Family.  Fort Collins, CO.

Mark is a dog-lover and it shows. I started with an immediate need for overnight visits while I was away on a mini-vacation.  He was able to provide this and sent me several pictures of my furry little beast over those 3 days. I also have ongoing needs for midday visits (walks) on some of my workdays. I know my sweet (and sometimes spicy!) girl is in good hands. I highly recommend their services!

M. Foster.  Fort Collins, CO

Mark is great. My dog, Milo, barely leaves my side and never likes to be left alone so I was nervous about leaving on vacation. Mark obviously loves and understands dogs and I could tell that my Milo was very comfortable with him. When I picked him up, he had clearly been well taken care of and had a great time. I would not hesitate to recommend On the Fly Pet Sitting to anyone! 

A. Katopodis.  Fort Collins, CO

Mark is awesome and our dogs absolutely love him!  Spend 5 minutes around the guy and you know he’s a real dog person.  We started with Mark when he was in Denver and we still take our dogs to Fort Collins (1+ hour drive) to stay with him. The younger of our 2 very high energy golden retrievers gets so excited to see Mark she literally pees as she sprints from the car to his door. 

Additionally, she had some food aggression issues and Mark had no problem navigating these. We get pics of the dogs on long hikes/swimming. Both the dogs come home worn out and happy. Highly recommend!

M. Wellens. Denver, CO

Cannot recommend Mark enough - he connected with our dogs immediately and they very quickly fell in love! He is truly the dog/pet whisperer. 

We feel at peace when our dogs are with him, knowing that they are in great hands of someone who understands and cares about their needs, as if they were his own. He is professional, reliable and invested in giving the best care and attention possible to his pet clients. We (and our dogs) are so lucky to have found Mark!

E. Jackson.  Fort Collins, CO

My husband and I were out of town for an extended period of time. Mark's rates were very reasonable, and he did a great job taking care of our cats.

L. Hill.  Fort Collins, CO

Highly recommend. My dogs are my family, not just pets, so I experienced a lot of anxiety around finding someone to be responsible for them while I was at work; then Mark entered the picture. He is obviously an animal person. He takes time to sit on the floor/couch and play with the dogs, getting to know each dog and their personality. He walks my dogs three times a week, consistently and reliably on schedule.

When I come home from work they are noticeably less stressed from being alone, because they had 40 - 60 minutes with Mark. And it's also very nice to get a mid-day picture of their adventures. My one Rat Terrier (Moxie, seen in left pic) is cautious around new people, sometimes not warming up to them for months. Within the second day, Moxie had decided that Mark was safe and a friend.

C. Rehberg.  Fort Collins, CO

From the moment that my husband and I met Mark, we could tell he loves animals and understands their personalities.  We had a bad experience with another pet sitter, but our experience with Mark put our minds at ease.  Now that we are working with Mark, it's wonderful to know that when we leave our pets and home, they are being well cared for.  

Not only did he care for our pets, but he also shoveled 16 inches of snow we received while we were gone.  We have a full house of pets, (3) dogs, (2) cats, (2) birds, and (1) snake.  Mark was able to handle all of them for an affordable price.  We will certainly used his services again, and we highly recommend him.

Lori and David O'Day.  Fort Collins, CO

For anyone that needs pet sitting, I'd like to recommend Mark from On The Fly Pet Sitting. My fur-babies were taken well care of, and I found him to be very professional and courteous. He clearly loves animals!!

L. Antonelli.  Fort Collins, CO. 

Finding Mark was life-changing! We have always boarded our two dogs at typical boarding facilities when traveling and it would be stressful for us, and our pups. We always chose places with video cameras because that was really the only peace of mind that the dogs were doing ok. It was a little depressing watching them sleep most of the day away in their pen, though. Our pups would be so anxious when we’d pick them up. 
Im so grateful that my husband recently found Mark’s business online. Mark boards a couple of dogs at a time in his own home, or if he is booked, he will come to your home for walks/feeding/playtime. We’ve had him watch our pups both ways and couldn’t be happier. He is very loving with our dogs, professional, accommodating and a great communicator - couldn’t ask for more!

The Krieger's. Denver, CO. 

Mark has been a wonderful help in my life.  He is reliable, communicative, and responsive. He has been available for some last minute requests and is super professional. He sends me messages and pictures from his walks with my dog Rue. He also tends to go above and beyond what is promised.  And on top of all that my dog loves him. Rue is wildly excited whenever he sees Mark. After time with Mark, Rue has a big smile on his face and it is clear that Rue has gotten a good deal of exercise and love. I am grateful to have such an experienced and reliable dog expert available to help when needed.  Thanks Mark!

M. Matter. Denver, CO. 

We feel so incredibly lucky to have found Mark at On the Fly Pet Sitting. Having just moved to Denver and needing to find a place to leave our dogs (that was not with family) for the first time in their seven years of life was a little nerve wracking for my husband and I. Our dogs, Perkins (Chocolate Lab) and Tucker (Ruby King Charles) and are like our kids at this point in life - very much spoiled and used to only being left in a place that felt like home to them - and we really didn't like the idea of having to leave them at a kennel, of any kind. With Mark the dogs are treated like family, and get to make themselves at home not only in their spacious backyard but in their home as well. Not to mention get plenty of cuddles from the whole family during their stay. When we drop our dogs at Mark's house they can't wait to run inside and when we pick them up they act as if they didn't even miss us - Mark is truly the dog whisperer! We would not leave our dogs anywhere else and feel so fortunate to have found a second home for them through On the Fly Pet Sitting.

E. Davis.  Denver, CO. 

I'm so lucky to have found Mark Foley to dog sit my Malamute, Anouk. He's experienced, reliable and easy to work with. Anouk is shy and stubborn and the fact that Mark doesn't watch more than 1-4 dogs at a time is perfect for her. The dogs are free to run on the first floor of Mark's house and the back yard. Anouk always races to greet him when I drop her off and is tired and happy when I pick her up. Mark's family are also dog lovers and have been wonderful with Anouk. I'm so happy with On the Fly Pet Sitting and wouldn't take my dog anywhere else.

D. Sophia. Denver, CO.

Our three terriers are very particular dogs and they love Mark! The weekly walks and games of toss have been great for keeping them in contact but we especially love the overnight stays. Mark keeps us informed with notes and pics - especially on our longer trips. We recommend him highly!

J. Wisner. Denver, CO.

Working with Mark at On the Fly pet sitting has been so easy and convenient. Mark is incredibly easy-going and it is easy to tell that he has a genuine love for animals. I have a 4 month old puppy and a five year old dog who have very different needs. I find watching my puppy pretty challenging sometimes but it is never an issue for Mark! My dogs love his yard and I feel like they are getting their own little vacation when I'm out of town. Another huge plus is the price - I've normally paid around $55 for each dog, but Mark's fee's provide a huge cost savings for me. I highly recommend using Mark's services if you are going out of town and want your dog to be comfortable and happy!

S. Aud.  Denver, CO

Mark has been a Godsend to me and my two dogs. They are older and had lost their 'man'. Mark has been the best replacement for their loved 'man' and has made both of them happier, more well-adjusted and infinitely more playful.

Finding Mark and this service has allowed me the peace of mind to travel again knowing that he'll take care of them as if they belonged to him.  
I am beyond delighted with this man and the service he provides my family.

C. Goodis-Baker. Denver, CO.

We used On The Fly Pet Sitting recently when we were out of town. Mark and his family provided our dog Toby with amazing care and attention 24/7.. They took him on hikes, which he really enjoyed, and generally provided him with lots of love and play. Toby is a member of our family and we are usually anxious when we leave him but we could see that he he was having such a good time with Mark and his family that we were able to enjoy ourselves. I absolutely recommend On the Fly Pet Sitting and will be using them again shortly. I would not want to leave my dog with anyone else.

M. Brittan.  Denver, CO.

Mark created a great second home for our dog, Willy, over the long weekend. The team took care of our boy and brought him not only to the park, but on a hike and swimming. The only bad part was, we weren’t sure if Willy would want to come home with us after having such a fun time. We also loved getting a text photo update and hearing how lovingly Willy was welcomed at Mark’s house. We highly recommend On the Fly to other dog lovers!

A. Cornish-Maillet.  Denver, CO.

We were thrilled with the treatment Finn received and highly recommend Mark as a reliable  and caring pet sitter.  Finn let us know he enjoyed himself as well when he was reluctant to leave when it was time to pick him up.

J. Gypton.  Denver, CO. 

The benefit of working from home is that your dog gets to be with you 24/7.  The downside is that when you do need to board him, he is anxious, scared and completely unfamiliar with being placed in a kennel overnight.  This tends to make for a nightmare experience both for our dog and the big brand pet boarding services.

I recently used On the Fly Pet Sitting and was amazed by the experience.  As a boutique pet sitting service, the entire process was personalized to the needs of our dog.  Mark was kind, extraordinarily communicative about his hands on process, and most importantly genuinely concerned about the experience and care of our pet.  Rather than being one dog of 20, our lab was given individual attention for the duration of his stay.  From walks on the Cocheco, to playtime in the back yard with Mark, Otter was treated as if he was Mark's own dog. Upon pick up, we found our pet to be happy, tail wagging, and believe it or not, a little reluctant to leave.

On the Fly Pet Sitting will be our go to play to board our pets in the future.  Incredible value, hands on and caring experience.  Strongly recommended.

K. Tode. Exeter, NH.

We are so happy we found Mark Foley and On The Fly Per Sitting! Once we adopted our sweet Laila we knew she would need lots of love and attention, Mark has immensely helped to facilitate the care she needs when we are not able. He has always been reliable, easy going, and caring with Laila. She is so excited to see him every time, it makes my heart happy.

F. Bygd.  Dover, NH. 

I cannot say enough good things about Mark! He took care of my shepherd Maya who is a difficult dog and usually very leery and sometimes aggressive of new people but within seconds she licked Mark's face. His beautiful calm energy transfers onto the animals and Maya is living proof of it! Definitely my favorite place for my animals!

C. Stauber.  Morrisville, VT.

Loves our dogs! Very flexible and reliable!

J. Levesque-LaChance.  Dover, NH.

Mark does a great job. Thanks for taking such good care of our animals!

K. Morgan.  Dover, NH.

Mark is great. Flexible, relaxed, wonderful with the dogs and really gets them out for a good romp which I really appreciate!

N. O'Connor.  Dover, NH.

Mark is such a great resource. He is a relaxed guy- so he puts our pup MIRA at ease right away. It is so nice to pick her up and know how well she was cared for. No post kennel crazy here. She is at home with Mark and he will he our go-to guy when we go away!  Thanks Mark!

T. Piper.  Milton, NH.

Mark has been taking care of our 9 year old Chihuahua, named Peanut.  Everything is going very well.  Peanut is a normal dog, but he has a few special needs.  He has had cervical spine surgery. He can be very lovable, but he also can be a difficult dog.  We hired Mark as a dog walker three days per week to help break up Peanut's day while we work.  Mark is mellow, easy to get along with, and handles Peanut's special needs with ease.  Mark has a flexible schedule, responds immediately to our text/calls, and is very reliable. We are very happy to have found Mark, and look forward to working with him in the future.

J. Esposito and B. Fiske.  Dover, NH. 

I have known Mark for about 10 years.  We have fished, hung-out, and he has watched (fed-watered) my chickens.  Now he's watching our our dog and cat.  I have a huge, Greater Swiss Mountain Dog, and she's always got along with Mark.  If Mark says he'll be there, he will, and he'll do a great job. Don't hesitate to trust your furry kids with Mark.

L. Martin.  Dover, NH. 

We were Mark's first 'cat' client and we were so very impressed with his professionalism and love for animals. He was very conscientious and did a wonderful job of getting to know all six of our cats before we went on vacation. Two of our cats walk well on a harness, he tackled that with ease! We came home to a happy cat household. I would recommend Mark Foley to anyone that wants the best for their pets while they are away.

B. Kretchman.  Kittery Point, ME.

I highly recommended the services provided by On The Fly Pet Sitting.  My dog can be difficult at times, she barks a lot, chases cars and doesn't get along very well with other dogs. Asking someone to take care of her can be a challenge. As I searched I found Mark's blog on the Internet. After reading his blog and meeting with him I knew she would be in very caring and competent hands while I was away on vacation. Mark got her, like we get her. He cared for our dog as if she were his own.  

I cannot express how much I appreciate his services. I will not hesitate to call him the next time I need a dog sitter.  I would highly recommend him to anyone.

Thanks again for taking such good care of Sadie for us.

J. Zagar. Dover, NH.

Let me start by saying that Mark Foley with On The Fly Pet Sitting provides consummate professional care for your pet and I would highly recommend his service to any of our friends or family.

We have a small dog, Cobie, who is almost 10 years old and has special needs.  Our dog had a severe illness a year ago and as a result was diagnosed with diabetes and requires particular care.  He is on a regimented schedule of feedings, insulin injections, and exercise, so his supervision is more complicated than the average pet.

We recently decided to take an extended vacation overseas and it was the first time we left the dog since he became ill.  Needless to say, we were feeling anxious about handing over that care to someone else for two weeks. 

We didn’t need to worry with Mark on the job…

Mark is, in a word, amazing.  He loves animals and is trustworthy, conscientious, responsible, and kind.  Although he already has certifications in pet CPR and first aid, he went the extra step and researched canine diabetes and is a pro at the injections/medication administrations. We were truly impressed because it was difficult for us to get the hang of regulating our dog and I’m a nurse.

We flew Mark to Arizona from New Hampshire and he house sat for us as well.  At the conclusion of our travels we arrived home to find the dog and house in perfect shape.  I don’t think the dog even missed us! Cobie and Mark formed a special bond and it was a wonderful experience for us all.

Thanks, Mark!  We loved having you here and look forward to the next time we get to see you.  Cobie misses his morning strolls with you and is still checking your room to see if he can come in for a cuddle or a treat.
If you are looking for someone who will love your pet(s) and treat them as well as you do then you’ve found that person in Mark Foley.

M. Holliman.  Phoenix, AZ.

Video testimonial from Maya's owner: