>Do you know where I can get a boilerplate contract?

A boiler-plate contract will not solve your problems. i.e., you won't find something at staples that will work. Rather, you need to talk to a lawyer and get he/she to draft a template for your needs. I could do it for myself. However, if I did it for you, I would be practicing law without a license. The drafting of legal documents or documents that will be used for a legal purpose is considered to be the practice of law. I draft documents today, but only under the supervision if a lawyer admitted to the bar.

For a few hundred bucks, a lawyer should be able to help you. Alternatively, if somebody here has an existing agreement, there is no problem in them forwarding you a copy of that. Still, I would get your own lawyer to review the suitability of such a document.