I'm in college and I plan on recording some songs soon and I will be using some people on campus to play a string part on some songs. If I use these people should I pay them a one-time fee? Do they get a cut of sales? What if they did it for free, but I magically made it big and sold a lot of recordings, could they demand a cut of the pay?
What's the standard practice for this type of situation?
Best to talk things over with a good entertainment lawyer if you have any real concerns.
I do a lot of classical recordings for an out of state producer and he uses students for a lot of his work. He has them sign an agreement that they are being paid, up front, for their services and they agree that this is the ONLY money they will receive for the project. This contract also stipulates that are no residuals and they will not be getting a portion of the project pie sometime later on.
It is my guess that even after signing this document and having it witnessed that they could come back later, if the project went big, and sue for some of the profits but I don't think they would have a leg to stand on since they did the signing as adults (all over 18) and they were not coerced and they received money, in advance, for their agreed to services.
I am not a lawyer and what I am telling you is based only on what I know from this given situation. I would consult a real lawyer before undertaking this project. It could save you a lot of time and grief later on. (not to mention MONEY)
Money has a way of making enemys out of friends and what was said with a handshake and a smile is later forgotten or subject to memory corruption so it is best to get it all in writing with a witness.
Hope this helps.