Unfortunately, my parents have a high debt-to-income ratio, which is preventing them from securing a loan to buy the house.

Investing in the right guidance early on can prevent major issues later and give you peace of mind as your portfolio grows.Wishing you continued success on your journey!

So not every time it goes south can it be prevented.   

You should also ask for estoppel certificates signed by tenants, which confirm lease terms and prevent disputes later.

We've really like kwikset 816 key control deadbolt ($38-$45) with passage handles-- we ALWAYS remove keyed entry handles to prevent lockouts.These 816 Landlord Locks have a hidden cylinder for a master key and an easy to rekey "smart" tenant lock. 

You may want to review your contract and consider consulting a Tennessee real estate or hospitality attorney to clarify your rights, especially if you want to take back control and prevent losing those bookings.Hope this helps and good luck getting this sorted!

What is keeping this house preventing you from doing?

This will prevent them changing their mind later, and may reduce the ownership timeframe to file AP.3) Consider recording the QC deed (atty advice on this) and then pay the back taxes and put my mailing info for future bills.Once you've done the above I'd rent the home, pay taxes etc for the next how ever many years and then file you AP claim when the time is right.

In FL law, there are only certain reasons why a seller can cancel a contract (buyer can't get financing, force majeure, mutual agreement of both parties, title issues, etc)- Can this 2nd position lien holder prevent the sale of the property, even though the sale was allegedly agreed upon by the primary lien holder?  

On a Commercial loan, most lenders will require a good faith deposit to prevent you from shopping.