The work around in most local jurisdictions for circumventing landlord/tenant laws where tenants are harder to evict is once it is a contract of 1+ month in length. Per my lawyer, signing multiple contracts at any periods of less than 1 month will restart this time frame, and avoid lengthy court appearances for evictions. I suggest that we have the option to send out multiple renter agreements to guests if the stays are greater than 1+ months.
Disclaimer: I am not a lawyer and am unable to provide legal advice. This is only per my discussion with a lawyer and my knowledge of this topic.
I love this idea. We often have multiple month guests who would like to pay monthly as well, so this would solve both problems, potentially, and allow for a payment at the beginning of each month, much like a long-term rent.