Renter’s agreement for owner occupied home

[Karen L.]

I’m a home owner in California looking to rent a room to a coworker. We know each other a bit, so I want to keep the living space hospitable and friendly for both of us. I’ve used a basic roommate agreement in the past. This wasn’t a lease agreement though. More like agreed to house conduct.

Is there any legal requirement to have me (the owner) and renter sign anything? Is it prudent to put anything like house rules, rent amount and due date, etc. in writing? Any suggestions on whether an agreement of this sort is a good idea?

Thank you in advance for your feedback!