Where are you located? Have you been using Craigslist or Auction sites for your search? If you are in an area with snow/salted roads, consider travel to an area that does not have it. (CA, AZ, WA, OR, FL,etc).
When you do find something you might like, get as much info on it as possible, there are a lot of great buses out there, but a few to stay away from. To start with, Caterpillar engine buses are not highly regarded here.
But the biggest thing that will cost you more time, money and headaches than anything else, is RUST! If you have to fly and then drive it back, it is worth it to avoid a bus that has rust. The money you spend will pay you back many times over if you get a rust free bus.
Well happy hunting and let us know how it turns out, or if you need advise on a bus you might want to buy.