When removing one person, you do need to be sure the remaining Tenant(s) still meets your income requirements.You should also have a clause in your Rental Agreement limiting "visitors" to two weeks, with specified penalty for exceeding without prior written authority.You should always have all adult occupants named on the Rental Agreement, no exceptions.

If your tenant wants to remain in good standing with Section 8 policies they have to comply with the lease.  

I would simply tell him - in writing - that I am listing the home for sale and the lease will remain month-to-month until it is sold or he chooses to move out.Don't communicate with him except in writing.

But we have remained debt free & retired for decades & have never had a mortgage on any of our homes or any of the investment properties we own, (but we still hold seller financed notes on the majority we have sold). 

If you give notice and they remain in the home beyond the termination date, then the next step would be to evict.

Without that, you could estimate what the remaining time would be based on the original starting amount (public record) and then just do a 30 year amortization with the approximate interest rate at that time

Thus, my own bias of course, I think the best use remains residential.Is it possible to challenge or request a second opinion on the appraisals "best use"?  

It is very important to understand what you are purchasing at the sale and whether there may be any liens remaining on the property.

The attraction to business investing however has remained low due largely to the unknowns.

I have since sold one lot for more money, and the remaining lots to a second buyer so with closing costs and such I will still be at the same profit margin.