Even if your lease permits showings, you can expect a fight based on COVID. 

-- Here is a list of potential pitfalls and diligence items: -Seems like a given, but first thing make sure the park is properly permitted -- certificate of zoning (e.g., legal as park, nonconforming, grandfather)-Master gas or electric?

We have been renting it out on Airbnb since about April when our STR permit was approved.

There are a few multi's that have sold in the area that give me an IDEA of a possible ARV but I don't know the build cost - permit costs and there aren't any vacant land comps that I can use to get an Idea of what to offer.Any suggestions?

RodriguesThere is some language from Fannie Mae in the following passage of D1-4.1-02a limited liability company (LLC), provided thatthe mortgage loan was purchased or securitized by Fannie Mae on or after June 1, 2016, andthe LLC is controlled by the original borrower or the original borrower owns a majority interest in the LLC, and if the transfer results in a permitted change of occupancy type to an investment property, such change does not violate the security instrument (for example, the 12 month occupancy requirement for a principal residence).The servicer must notify the borrower that a property transferred to an LLC must be transferred back to a natural person prior to any subsequent refinance application in order to meet Fannie Mae’s Selling Guide underwriting requirements.https://servicing-guide.fannie...It doesn't seem like you can close in an LLC, but you can possibly transfer it over immediately after the close.

Here's an example budget for a 1500 SF home with unfinished basement (not included):Land: $24,000Soft Costs (Architect, Engineering, permits, property taxes, insurance, loan interest)  $50,000Hard Construction: 1,500 * $95 + 750 * $65 (basement) = $192,000Sale Price: $330,000Transaction Costs: $30,000Net Profit: $58,000 (just under $40 per SF)

I would also be sure to check local laws, HOAs, etc. to see if they permit renting out rooms like this.  

Build a cottage/bath in our backyard (w/ full permits) and use it for short-term rental via Air BnB.

How are you going to administer contracting for repairs or improvements, building permits may require the owner of record, in title to obtain permits.

Real estate sales signs are only permitted on the property being sold/leased/rented.