I’m going to assume you aren’t a legal expert, but you trust this thing to write legally binding contracts that may accidentally use words and phrasing that do something different than you expect?

I seriously doubt GPT understands which laws and case laws apply to which areas. It could be creating a contract that does something you don’t want or even a one that isn’t enforceable.

Pay a lawyer. There’s a lot to gain if you do and a lot to lose if you don’t.