I've asked people to look after my place in exchange for the housing and whatever is in the fridge, with no money changing hands- not really hard to find a nice college student who is thrilled to have a week of peace & quiet, away from roommates or parents with a good entertainment system, strong internet service and minimal chores - but it never once crossed my mind to charge someone for the privilege of watering my plants, bringing in the mail and tending to the needy ass cat.