There were a lot of hurtles to overcome and really struggled with getting the bank to understand what potential there was in short-term rentals.

Management costs will be high and you'll likely struggle to find anyone to help with such a small park.

It is a struggle for sure!

Its a struggle I have had to deal with when purchasing inherited tenants as well.   

If you're struggling with your existing lender then call 20 other lenders in your area and find one that works for you.

They are a linear step up from a SFR, then Duplex, then Quad, then 8 and so on, but the thing that constrains the small multi class is that they struggle to qualify for any kind of advantageous financing (like a FHA loan on a 4-plex or a Fannie Mac or Freddie Mac small balance loan on a more valuable property), they don't have any sort of scale to allow much efficiency of management, and they typically experience a downgrade in tenant class.As a result of ^^ they can trade more slowly and perform less optimally. 

Struggling to decide the route to take in order to have increased protection against liability.

Businesses, particularly small businesses, have struggled as well.

It was a struggle as the owner thought it was worth more.

He has been struggling to pay the rent and his pickup payments etc. so he has decided to move back in with his parents until he can get his pickup caught up and the business going strong enough to support him.I really appreciate both of your input and I'm very glad that I followed your recommendations and talked to him.