Wholesaling REO contract to end buyer???

[Dave Smih]

ok so I have a property under contract and I have and end buyer what contract do I use to get the end buyer locked up. and will this contract be the same if i want to assign it or quit claim it. any info would greatly help me I want to secure a deposit and I need to know how to handle this and seem professional in doing so.

thanks you guys are great and have helped me so much already