Wholesaling contract law

[Shashank Gokhale]

Whoever a contract is filled out and signed by both parties, does that contract absolutely specify what the terms are, or can the state where the contract applies override the terms in the contract?  For example, I am a wholesaler in Texas.  If I draw up a real estate contract (signed by both parties) that does not mention some of the things in Texas' real estate contract, then would the Texas Real estate contract override what is in my contract?  Specifically, if the TX contract says an option period can only be offered when a fee is paid, and my contract just says "Seller agrees that buyer has a 7 day option period", then is a fee still owed just because it was required in the Texas contract?