I am soon going to be a new landlord.The two family house that I am buying needs the sheet rock from the lower unit to be gutted and new sheetrock installed.

At the price point of $600 a month, is this a lower income tenant base?

You can also find out the pay-off amount to see if it's worthwhile to just pay it off.Then, it's just an additional expense (and lower utilities for you and/or your tenants)

Lower Manhattan has seen great Commercial to Residential conversion as a result.

Scenario A (typical) - $500k duplex-$125k down-$375k mortgage at 4.6%Scenario B (modular financing) - $500k duplex-$125k down-$260k mortgage at 4.6%-$75k HELOC on primary residence-$40k loan against 401(k) (technically this would be $165k down, but you get the point)In scenario A, paying off the mortgage quickly makes zero improvement on cashflow until you pay it off completely, or refinance, and there's no point in that if your rate is locked in lower than current(or future) market rates.Scenario B could involve higher interest rates on the HELOC and the 401k loan, but you have multiple, simple, easy options for increasing your cashflow, and then you don't end up playing as much in the overpriced, volatile stock market.

Peter would depend what your current liquidity and net worth is along with your annual income from your job/business/current investments etc.Different assets are cycling at different points in time in different states.2009 was mainly coming off the bottom for the lower priced SFR assets. 

Is it lower income?

I have not, over my career, seen modular able to come in lower cost than site built, assuming you have good subs on a site built property.

I do not want to start out with lower rent, I fear them moving our in a year when there lease is up and having a half finished basement. 

Your Vacancy Reserves Amount is lower than I like to maintain.