Presuming this is long-term contract (3-6 months), you basically are going through same process as employee - need to interview the company first, need to read

Presuming this is long-term contract (3-6 months), you basically are going through same process as employee - need to interview the company first, need to read the contract, and not sign it if it's not acceptable. If they're asking you for stuff that's not in the contract, say no. If they persist, walk away.