Pet sitting can be great fun and great income but there are a lot of important things to consider before starting in this business!
The most important thing to consider is how much you really know about animal health care. Can you recognize subtle signs of illness in every type of pet that you will be watching? Many pet sitters have a background in the veterinary world for this very reason. There are so many things that can go wrong with animals and many animals (cats especially) can be very stoic and not show when they don't feel well.
Going along with the above, you need to have plans in place for if one of your charges does come down with illness. If you have to rush someone's pet to an emergency clinic at 7:00 am on a holiday how will that bill be paid? Who will make decisions on how to treat that animal? Do you know where the animal's normal vet is located? Do you know where the closest emergency vet is located? Do you know the animal's previous medical history.
Also keep in mind that there may be people who are displeased with your services at some point. How will you deal with this? Are you planning on becoming bonded and insured in case someone tries to sue you?
Do you have a reliable person who could fill in for you in case of emergency where you cannot make it to the job?
This is just a short list of things to consider. I don't mean to be discouraging, but pet sitting is way more than just playing with cute animals all day
It's one thing if you are just going to be feeding your aunt's, or friend's, or neighbor's cat for 2 days but it's a whole 'nother ball game if you are advertising yourself as a pet sitter to the general public!