When thinking about rents, your materials should be about the same across - but labor won't be.

This leads to another point, if I'm selling to Joe Average, I allow all kinds of mistakes, errors or blunders, but if I'm dealing with an "investor" they should be more aware of their obligations and how to proceed under contract.

Repairs done by Landlord will be billed by the job or as labor plus materials."

Keep in mind that fourplex owners are typically more sophisticated that your average homeowner, so you may not find the screaming deals that you would find if you were approaching Average Joe and Jane Homeowner.

Hope that helps...Joe

Now that is just material cost not my labor.  

If not completed then give them a notice of lease violation - unauthorized occupant, if not corrected you will file for eviction. 3 day's is max for visitor unless pre-authorized.If they say well (Joe is only here for another 2 days ask to see Joe's proof of residency, before you agree to another day).As far as charging extra for extra person on rent amount, unless it's in the lease to begin with it's not something you'll be able to add without an addendum.

If city gets involved you'll be paying a legitimate company to do what some say laborers can do on a Saturday with a dumpster.

@Joe EbanksYou're looking for mortgages and satisfactions.

Contractors that want money for labor up front can take a walk.