Any form of real estate is fine.

Pipe was fine..

Sharing the concern about freezing it is fine; its all about building a relationship, getting buy in vs. rules.

I mean if people stopped paying the chance of them repaying is not all that great it happens of course but the chance of then going back to bad behavior is very high.. if you get them to work out fine. .but you certainly go into this knowing that your going to own a lot of real estate.. 

If you want to buy in the name of the entity, that is fine, but they will also pull your credit and the credit of any significant partners you have.

I'm now hearing an unpermitted bathroom could cause issues with insurance claims, city fines, and resale.

It is perfectly fine for it to purchase a property with another entity as tenants in common. 

I FAIRLY WELL OFF AND DOING FINE BUT THAT DOESN'T MEAN I AM GOING TO SPEND $100,000 MORE FOR A STEEL BUILT HOME JUST TO SAY "HEY LOOK I PURCHESED THIS IN AMERICA AND GOT TOOK".

Sure, you can put 10% down if you'll call the place a second home (STR is totally fine for that), but your pricing (again, rate and points options) is much higher when you put less than 10% down, and you'll have mortgage insurance for a while as well. 

Amortizing over 30 is usually fine but they will likely want a balloon (payoff) in the near future.