Is a tip expected or typically given to sitters?

I wouldn't say it's expected. It's always appreciated. Some clients tip and some don't. Beyond tips, some give gifts, some post great reviews, and some promote referral business.

Sadly, folks rarely tip despite me going above and beyond every single visit. I still offer great service, but I am surprised I don't get more tips. When I hire a dog sitter I almost always tip with a nice note of thanks. I am sure it helps me to always get their time and probably better care.