I sell 2 different prices for beats I've already made. I have an exclusive price for $200, but that's more for serious cats. For people who might not have that kind of bread to spend on just one beat, I have the leasing option which is only $50. It's easier if you have 2 different markets to attract different people.
Ya, good point Fieva and bknot1. Have an exclusive price and a lease price. The lease price is cheaper because you can sell the track to other clients. Your just leasing the beat to them. It's kind of like leasing a car, you can lease it to someone else latter. Now, that does turn some cats off from buying the beat. But, if they want an exclusive beat, it will cost more becuse you can only sell it to one person. Try to find only serious artists that want to buy beats. And also have your "TERMS' in writing so that your client knows everything that goes into the sell.
Here's an example of production terms:
http://www.beatsbuy.com/termofuse/index.html
Always make sure the artist knows what he/she is getting and info on leasing and exclusive rights.