The time for them to negotiate the price was when they got the appraisal done-they didn't, so too bad.Two choices-take the $5K and relist with a new realtor or negotiate with them for the $24K they are short. 

We don't know if the new regime will be retroactive.In short, we don't know anything.

In short, you need to stay there a year as an owner-occupant and then you refinance into a conventional, rent both units and then you can use the FHA to do it again on a new one.

I wouldn't recommend trying to do something like this right off the bat, I think you need to get into the game and really know what you are doing before taking on that level of risk.Happy to chat more over a phone call or direct message if you want more insights or have more specific questions!

I’m also aware there could be tax advantages to running a rental business, which could help offset the shortfall.I’ve had experience with short-term rentals in the past, but I found them to be a headache.

Also consider short term month-month leases on airbnb, renting individual rooms, month to month leases, just to get the cashflow energy flowing again.  

Fell into a short term vacation property and can't wait to do more investments!

I intend to rent out my current home as a short-term rental.

This is a numbers game.

They are inexpensive, they usually come with mineral rights (big plus in Texas), they typically have short redemption periods, low rehab costs, and sell quickly at the right price; they also have large ROI.