I normally advise my clients in Florida in this situation to:1) give proper notice of non-renewal, and at the same time,2) give notice to pay.If tenant doesn't pay within the notice period, file eviction, and the non-renewal notice serves as a "back stop", if you will, in the eviction, in case you needed to amend the complaint to add that count to the action. 

I currently pay $1600 a month.

What are your thoughts on paying for mentorship?

Also do you know where to buy, how much to pay? 

(Not all pay all cash)Cash buyers wants to be found.  

I am aware that if the property gets sold at higher amount than the upset price, the surplus amount is used to pay off any junior liens and the left over goes to the owner.Will the surplus amount be used to pay off property tax liens and HOA liens? 

Appraisals are subjective and don't necessarily reflect what a similar property could be purchased for if you're looking hard enough or if you have the ability to pay all cash and depends on how motivated the seller is and also the venue you are purchasing from or way you are obtaining title

Some of the adjustable products, the payment stays the same, but the principal to interest allocation changes to the point where people are only paying interest and are now in a negative amortization where the amount they owe is actually going up.

Give it a solid 2 weeks before you sign up for anything or pay anyone any money. 

It's free, no pay wall etc.