We used a trusted friend, 20 years old to watch our dog and house for a week. When we returned, one of the neighbors asked if we had a graduation party, since there were cars lining both sides of the street for a block or more. We found a burned counter top from a curling iron in the master bedroom, bottle caps in the garbage disposal and couch, and orange juice stains probably from mixed drinks. When my wife asked her about it, she denied, denied, denied, and was very upset. We're on good terms now, 15 years later, but it was pretty amazing.
Ironically, we just had a dog/house sitter this week for two nights. And loaned our house to friends with 3 young kids for two nights. Tomorrow we return, hope there is little damage, but I have learned to expect it.
On the other hand, I have considered house sitting, but have not done it yet. Sounds interesting and may save some money, but I am guessing some PITA items as well. At this point, money is not a big motivator for me.