My name is XXXXX XXXXX I'd be happy to answer your questions today.Fl. Stat., Section 83.52
imposes upon a tenant to (among other things):
(1) Comply with all obligations imposed upon tenants by applicable provisions of building, housing, and health codes.(2) Keep that part of the premises which he or she occupies and uses clean and sanitary.(3) Remove from the tenant’s dwelling unit all garbage in a clean and sanitary manner.(4) Keep all plumbing fixtures in the dwelling unit or used by the tenant clean and sanitary and in repair.
Unless there is a local housing code ordinance that limits the number of people who can live in a unit, just having someone sleep in the dining room isn't per se a violation. But they are required to keep the premises clean and sanitary.
If the lease is only for two people, having a third person live in the property without consent is a violation of the lease, and they could be ordered to remove the third party for that reason. Look to see if the lease says they need consent to have others live there (most form leases do).
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