That being said, I want to waste no time in figuring out what the next best move would be, especially as someone who's interested in the buy-and-hold strategy and in managing my own properties (at least in the beginning). 

There is a possibility I can get 3 houses for under 10k each but they aren't for sale and I would have to direct market to the owners.

Fannie Homestyle requires 25% down and is only for 1 unit investment properties.

Last year was a slow year for airbnb and I was considering switching it back to LTR but this year has been high occupancy and bringing in $3000s in summer and $2000s in fall/winter, huge jump. 

Now fast forward 4 years, I found a potential good deal in a way better neighborhood that the wife and I want to move to.

The answers could change with additional information and I do not recommend you use the above without consulting your a tax professional first.

I manage both long-term rentals (LTRs) and STRs, currently operating seven STRs, all of which are profitable.

The rental market is very strong in Middlesex County - I have a rental here myself and work with a local property management company.

But like Edwin Watson -- I am a local investor/agent here in Indianapolis -- and I have also driven by their properties and they seem to be great quality. 

And I hear Medellin is booming.