Knows real estate tax write-offs and how I can best apply them!

if it is a BRRRR you'd pay the seller off when you refinanced into long term debt, either conventional or DSCR.i don't know anything about the location, market, etc. but if it needs a 40K rehab, you need to push the purchase price even lower than 140K, or it will not work as a BRRRR. 

- The percentage difference is the percentage the taxes will go up after you buy it.What do you mean by the property has HVAC AND boilers? 

You can use the "bad roof" or other problem to negotiate a lower purchase price. 

The numbers may be 30-40% lower than today's cost, but the process/approach to estimating may be good for you to review.

Who is your market for lower cost housing.  

Many people get this confused thinking that is take-home (NET) income, when it should be BEFORE taxes GROSS income. 2.

In this case, your monthly payment with 20% down will have a good MARKET rate if your DTI works with a much lower month payment and no mortgage insurance(MI).

LTRs with long term conventional financing and standard management aren't really cash flowing anywhere right now. sure, there are lower cost markets that look better on paper, but there are costs associated with those supposedly cheap markets as well - deferred maintenance, more challenging tenant base, higher cost turnovers as a percentage of the rent.2. i wouldn't pick a random market thousands of miles away based solely on statistics or numbers. 

Others wont touch anything lower than $500 in cash flow.