Just keep a good record of your SREO and hang onto the HUDs that you've had from both your purchase and your sales.

I’m looking to raise $160,000 to cover the purchase, renovation, and activation of this new Airbnb property.

The only two ways to rectify this are (1) purchase the property far below market price or (2) significantly increase the property net income usually through some method of “repositioning”. 

You can purchase a primary home with seller financing, then rent out the spare rooms to generate income.

You can find some 2 units under or around $250K but they have been sitting on the market for over 150 days which tells you its not a great deal if it were an investor woud have already purchased it 4 month ago.  

Step 1: Get preapproved for an FHA loan for the purchase price you are looking for.Step 2: Connect with builders until you find a few that will finance the construction of your home. 

I have helped many new investors purchase their first property in Memphis and LIT.

So, you can do a land contract for 12 months, which should allow lender to credit you full value of the land vs the purchase price, but the loan will pay off the land contract, so the lender maintains first lien position.Can't help you with the rest of your question, but you should be able to search for "CPA" here on BP to find experts to reach out to.

I wouldnt give any consideration to what the seller needs in order to break even in determining the purchase price.

Now days you don't buy a deal you make the deal either with how you operate the property, how you finance the property, or how you purchase the property.