What paperwork do you need to hire a GC?

[Charles Zhou]

Hi everyone - this is first time for us to hire a GC. We are hiring one to do some cosmetic rehab on a unit of our multifamily property. 

J Scott's book mentions a few documents to prepare, such as W-9, Independent Contractor Agreement and SOW. However, in our case, besides the estimate we received from the GC, we don't have any other documents yet to specify any other project details. Do we need to sign a contract with our GC? Who prepares the contract, the client or the GC? 

What paperwork do you sign when you hire a GC? What details do you specify in the contract?

Thanks for all your help.