I have an older cat & a 4 year old rambunctious German Shepherd & I use a commercial pet sitter for overnight visits plus day visits to let the dog out. She goes way above & beyond - cleans my house, sweeps up my patio, etc. So, yeah, I tip hugely - sometimes up to 50%. I don't think she actually makes much money after the agency gets their cut and she's newly married & struggling a bit financially.

It's worth it, to me, to have somebody uber-reliable so that I do not have to worry about the four-leggers. Sometimes pet sitting is almost as much as my hotel, but that's life.