Speaking of house-sitting, one of the most useful gifts you can give—and also one of the most cost-effective—is helping around the home. To be clear: This isn't a cutesy "I will clear up after 1 dinner" IOU. For max effectiveness (and gratitude), you need to promise something that will actually save the recipient time and effort. Giving the gift of time could actually make its recipient happier than a physical present would. So if you intend to clean, then clean the entire house. Or take care of a nagging chore that the giftee really means to tackle, but might not get done without your aid: Washing windows, repairing nail-holes, clearing gutters, shampooing carpets, or even painting a room.