Three duplexes or one six-unit property???

[Andrew Palumbo]

Hello all, my brother and I own a total of 3 properties with a 4th under agreement (has not closed yet - fingers crossed). Working on another deal where the current owner had 3 duplexes and changed the deed to a 6 unit multifamily to save on taxes. Looking for input on a couple of topics -

Do we evaluate the deal as three individual duplexes or as a six unit property? 

We've never done a commercial loan as all current properties are 4 units or less. Looking for input on how to get a commercial loan and evaluate the deal from that perspective. I have only evaluated using conventional loan numbers. 

Located in Mass

Thanks in advance!