It seems a little steep.

*********************************************B) 3 Duplexes - two story, 1990's construction with roofs less than 2 years old, HVACs less than 5 years old,, each side is a 1000 square feet 2 bedroom, 1.5 bath unit - $345,000 (or $115,000 each).  

Just saw a episode of Judge Judy.. similar situation.. and yes,, the insulation needs to come out. you could get additional quotes,  remove brush, trash from exterior, any tree limbs that touch building, get exterminator in to bait and trap. next will be holes thru the ceiling from the rats.. any holes or vantage points on roof they are gaining access from, by A/C unit or vents that are damaged.. they are getting in some how and food source is active enough to keep them. 

I've seen them mounted on the side of a 2nd story or mounted on the roof.

How old is the roof, furnaces etc.Vacancy?

Hi @Robert Burns,Generally speaking the seller wouldn't have a back out clause due to an inspection (He/She owns the joint), not like they are now going to find out the roof is newer than they thought and now want more money.

Roof: Good - approx 8-10 years oldWater Heater: Good - 2006My thoughtsBy my estimate I'll cash flow approx $400/mo with 45% Cash on Cash.

I think I will stick with my Single families where i can get $200-300/mo positive on 15 year financing, and be quite liquid if i need to sell one here or there, with good management in place it really doesnt matter if they are all under 1 roof or you own a bunch of roofs, it just runs with little intervention.    

What about replacing the roof?

I'm not that cheap to where I'd rather save a few bucks today vs. having a roof I won't have to fix for 25+ years.