Everything seems to check out just fine.

You can always check with park managers and owners in surrounding mobile home parks as well as mobile home dealerships.

Landlords can conduct credit and background checks and have applicants submit  pay stubs and any other qualifications they may require of any applicant. 

If you tell them please to clean the same day as the guests check out.

Context: My dad has assorted health issues that limit his physical abilities and does not want to fill out forms or devote much time beyond discussing things with a Lead, reading over anything he’s signing, and sending a check.

I’m losing out on the opportunity costs if I would have left my money in these retirement accounts is what the critics tell me for tapping into my retirement funds and borrowing from them.

I am unaware of any state that does not allow you to collect advanced rent, but I am not an expert in all states.But you are typically required to deposit that advance rent in an escrow-type account. 

You'd need to know the laws around abandoned property in your state, should be easy enough to google or check with your attorney.

I am using my own money, sitting in my checking account, and loaning it privately to individuals who I deem qualified to borrow it.  

You'll still likely get some lower taxes, since some of the gain will be accrued in another state, but you still need a good tax accountant here.3.