Judy,
It varies, some on TUG do, some don't.
Personally, I do, and I use a cheapie template purchased from TimeSharing Today. I think it was only $25 several years ago. Then I've edited the contract over the years as needed.
In fact, lots of pointers in the Sticky section at the top of this forum
here, just in case you haven't seen it.
I believe the contract provides renters as well as rentors some sense of comfort that they have details written down and signed by both parties.