Will there be deferred maintenance expenses in the near future (roof, HVAC, etc)? 

In my case it was an incorrect roofing for low slopes that hadn't been stressed tested like this season.

I would say bank statements, taxes, rent roll, leases, utility bills, worker contracts, 12 months of maintenance logs, capex report (age of roof/mechanicals), and a trusted local property manager of your own to help you review your data.  

E.g. the roof is 10 years old, has 15 more years of expected life, expected cost is $XX, amortize that over the 15 years.It's obviously a lot of work, but you'll get a good sense of what the expenses will really be.If your gross rents are $3200/month, or $38,400/year, the 50% rule would expect $19,200/year in expenses before debt service.

The roof, furnace, windows, copper piping &  100 Amp service w/breakers are newer (don't know if that includes wiring throughout).The house is about 15 minute walk to the university area.

I have someone willing to lend me the closing and down deposit repayment terms 5 years. now when i run my numbers the property cash flows $544 monthly that 544 would go to the person lending me the money meaning first 5 years i would have 0 cashflow. is this a smart move or dangerous. i see it as since everything is fairly new and my current property manager manages this property as well i would add another duplex to my portfolio with 0 cost to me more details about the property below One furnace new in 2014Newer water heatersNew Roof 2015New Electrical service 2015Exterior painted 2015All New windows 2014New Kitchens 2014

Why not hire a home inspector that is knowledgeable about roofs.

I have someone willing to lend me the closing and down deposit repayment terms 5 years.now when i run my numbers the property cash flows $544 monthly that 544 would go to the person lending me the money meaning first 5 years i would have 0 cashflow. is this a smart move or dangerous. i see it as since everything is fairly new and my current property manager manages this property as well i would add another duplex to my portfolio with 0 cost to me more details about the property below One furnace new in 2014Newer water heatersNew Roof 2015New Electrical service 2015Exterior painted 2015All New windows 2014New Kitchens 2014

Other companies require that houses built more than 25 yrs. ago have updates to the electrical, plumbing, roof, and heating. 

What about the % being put away for things like repairs or future capX items like hvac or roof (although it's new now, something could happen that would warrant replacement).