Also, every house comes furnished and a lot of accommodating for different items that would never be considered in the US, i.e. negotiating hard/soft bed, larger fridge, installing oven & installing a dryer. 

If so, can you tell me the approx cost for the kitchen and bathroom to accommodate folks confined to a wheelchair?

There is no way they can require you to rip up more of your basement to accommodate them let alone you pay for it. 

If you can rent the other 3 together to accommodate bigger groups, you can command a higher price. 

Turns out he owes money on the car and does not have comprehensive insurance.

Are these vehicles looked at the same way as your standard rental car, or do they have unique, accommodation-type requirements to fulfill?

See HUD section entitle "Reasonable Accommodations Under the Fair Housing Act", especially the second to last sentence in the quoted section: "An assistance animal is not a pet.

I like his lease due to its clarity and comprehensiveness. 

Marc Winter your daughters may be different but if my parents offered me free rent or living accommodations I’d do that in a heartbeat over paying 2500 rent.Unfortunately my entire family lives in the cold Midwest and after moving away at 18, I’m not about to go back there.

Because I think reasonable accommodation will have fewer tenant changes, less damage and higher rents.