I can tell you from experience....you will not be able to distinguish one property from another after 3 to 4 properties, and most agents will limit you to that many per outing because of that.

Do you know what exactly would distinguish a 1 unit vs. 2 units?  

Linda Weygant I can hear every single step and can distinguish who's walking (married couple with two kids).

@Andrew Larson , once you have more than one member in an LLC no Court can attach orders against it - because the second member distinguishes it from your person.

to number #1: I do not try to distinguish one source of profit from another.  

There's no way to distinguish between a dated blocked because of a guest stay and a date blocked because the hosts are living there then.

"I print this close as possible handwrittenUse a yellow paperEnvelop is 4x6 with bright colorI hot glue a penny outside the envelope (distinguishing my letter from the rest)  I put a 49 stamp unique and a 21 cent stamp (21 cents is for the machine to not rip the penny out of the envelope) Any advice would be great. 

Just the other day I toured a modular home that was almost complete and it was very difficult to distinguish it from a site stick built house.

@Nicholas Covington Really appreciate you taking the time to distinguish PMI and MIP for me.  

But the only way you will know this is if you seen enough properties in that area to be able to start distinguishing the lousy ones vs well managed Condos.- Home Inspection, area potential, crime rate, School districts, etc.