This would increase your returns and lower your taxes by spreading the gain over several years. 

Any telephone conversations, correspondence submitted via US mail fall into the categories of wire fraud and mail fraud.Without the permission of the mortgage company there is no way to legally do this.

Just send you DMs/connection requests about this very thing!

A lot of what I've read on STRs says to use AirDNA data in your analysis, so I'm wondering if this is just a lack of understanding on my part. 

I would be curious to hear people's feedback on this.

If you're talking about building an interior wall to create a bedroom, this could work so long as you aren't significantly reducing living space compared to the competitive rentals. 3 bedrooms with a tiny living area could cause problems.

Worked with an agent via a referral and landed this centrally located home that comes with a 1BR/1BA casita in the back.

Plus, they can give you the lowdown on the whole process and help you every step of the way.You've got this!

My primary now will sell for $750k, I owe $290k, this will allow me to buy 2 $400k homes. 

This approach allows you to reduce living costs while recycling capital for future investments.Good luck!