I don’t bother with it in Arkansas or with our condo in Panama, but in California. . . Yikes.
There are some peculiar Landlord/Tenant laws in California and as you might imagine they are generally in favor of the tenant.
If someone stays more than 30 days you might have a problem getting rid of them. EVER!
You can find free lease forms on the internet specific for your state. You might even consider consulting with a law student…
I have used this site from time to time for about 25 years and found it useful.
https://www.lectlaw.com/formb.html