As the title says, but with these details:
I have a rental unit; this situation has come up with a potential tenant. This tenant has an adult daughter, who, the tenant volunteered, has an unstable lifestyle. So, said daughter will be staying in the unit from time to time as a guest -- not an occupant on the lease.
For warned is forearmed, so I intent to add an addendum to the lease stipulating the maximum amount of time a guest can stay on the premises.
The question is, how long should that be? I don't want to be unreasonable, but I do want to avoid her staying so long it becomes "where she lives". Also, should this be a maximum number of days in a row, or a percentage of the lease period? Or both?
Edit, to clarify:
I'm asking about what would be reasonable/customary/expected for a guest limitation to add to the lease, not about legalities (other than if I'm restricted from adding such a stipulation, which I don't think I am), or remedies if I wanted them gone.