They typically cost 35-45% less there and still offer delivery, some items were new in box even!

Some of your costs will be property taxes, maintenance, insurance, debt service if you get a loan, CapEx (replacing items such as roofs, AC systems, etc), vacancies, etc.

Charge against the security deposit to remove items left behind and for extra cleaning.

When in doubt, I'd say call and ask the tax assessor-collector.

If accepted I'll remove the heap and install a new Manufactured Home for about 80-90k including demo, site prep, ancillary items i.e. decks, steps, shed, carport and patio cover. 

I tried using one of those and ended up returning it because it did not work at all... not even sure why this item was for sale as it just spit the paint out in clumps.

Loan limits can increase by a factor of 3-5 in many of these cases, but this comes with a major tradeoff of 3-5 percent "compensating balances" (read more collateral via covenants or less money loaned in effect)Item 2 is desirable from the perspective of reducing brain damage and consolidating relationships.  

The REHAB number doesn't include "lost rent" and some other items like that.  

You do not deduct loan payoff amounts, loan payoff costs/fees/charges, and you do not deduct any operating items like prorated property taxes, prorated rents, HOA fees, etc. 

Those are the items that will kill you in this business if not taken care of up front, especially on a single family.