Remedies for Broken Appliances   If you are selling a home, you are often contractually obligated to make sure that all major appliances, such as water heaters, air conditioners, washing machines, oven/stoves/ranges, and refrigerators, are in good working condition. Overlooking this simple detail can cause deals to fall through or delay a closing.   If you do need to repair an appliance, check out www.repairclinic.com. The site, which sells appliance parts and accessories, also offers resources to assess mechanical problems, buy replacement parts, and fix the problem yourself.