If you're looking for a consultant to come in provide this analysis, there are a handful of people who do that on a regular basis.

I thought it would be seen as a regular business agreement.

Let me say EVERYTHING that Brother George Paiva said, make these inviolate rules.Let me add, hyperinflate the rent $50, and advertise regular rent.

If you ever watch income property they use a batt sound insulation quite regularly on their renovations.  

Most house fires start in the kitchen, here's an excerpt from our property rules:"STOVE, OVEN, AND RANGE HOOD: When cooking, Tenant agrees to use the range hood fan to clear cooking fumes out of the unit and to clean grease off appliances on a regular basis, as a build up of grease creates a fire hazard.

Once you form a impression of someone it you may be able to keep from reflecting it in your dialogue, but if often through in body language or tone.If you should end up in court for an eviction, the judge will likely be very sympathetic toward a handicapped owner who suddenly lost the property and has now become a tenant. 

The only downside is that someone (you) would have to check them monthly and on a regular basis to calculate usage and then reconcile that against the master meter bill, then subsequently print a statement with rent + water for the tenant to settle up each month.Good luck!

However, the new $2,500 threshold is good news for most small businesses who regularly purchase small equipment, furniture, etc.  

The thought of being a traditional agent with focusing on regular home buyers doesn’t attract me at all.

Does this person just visit on occasion or do they sleep there regularly.