If you hold it as a rental for 3+ years, you have created a tax liability that did not exist before.

They would grandfather in any existing homes that are licensed.  

I always thought it should have been outlawed and have no idea if it still exists in consumer loans.

Apparently it doesn't matter as they won't take any new ones, only renewal of existing.

Unlike STRs, a platform that analyzes vacancy, pricing, etc. does not exist. 

That would hurt the existing tenants who get kicked out! 

From my experience buyers typically prefer these lots because they will not have any neighbors directly behind them.I can't tell from your question if there is an existing house built, that you are purchasing, or if you are buying a lot and going to build on it.Also, you should have access to an interactive flood plain viewer to look where the 100, 500 and zone X for the flood plain are situated.

There's a really strong investor community which tends to be a great way to spread the word about existing Airbnbs coming for sale. 

I would also tweeker, I mean tweak, the non-existent application process.

When you purchase a home "subject to" the existing financing, that is when a mortgage stays in the sellers name.