I would not do a deal that costs me $770k and only grosses $72k a year.

However, on paper you have to depreciate it based on the 27.5 years, so your metric still looks good, but you took money out of your pocket to cover the cost.In my opinion, the only 2 "real" metrics, since are not easily manipulated are: gross rent multiplier at the time of acquisition and cashflow including principal pay down.  

If I were to rent out both units my gross rents would give me about $1700 above my mortgage payment.

You are going to have a 1.15 mil property, and you are only going to get 8500 gross a month, or 0.7% (not including cost of repairs you budgeted ).  

Our gross revenue for the year once stabilized should be around $210,000 per year.

The idea was that direct material and labor would be covered and any gross profit would contribute something to cover the overhead.

Income:$3,800 Gross Monthly Rent CollectedExpenses:Management $380 (10%)CapEx $228 (6%)Repairs $150 (4%)Vacancy $304 (8%)Wind/Hail $200 (5%)Property Taxes $200 (5%)P&I: $1,900 (50%)NET PROFIT = $450-500/MonthCash on Cash ROI: 8%LOAN DETAILS:Purchase Price: $350,000Downpayment: $70,000 (20%)Amortized Over: 20 YearsLoan Interest Rate: 5%Income-Expense Ratio: 1.08%Gross Rent Multiplier: 7.68

If they received 10% or 9,600 off of the gross and it will be less from non-payables etc. then not much money.

But with my dinky 5 VRs (which gross over 200k per year thanks to my iPhone and Gatlinburg Pigeon Forge) I’m happy using AirBnB and VRBO and I even have past guests book through the sites.

The garages,  $150 ea. or more, per craigslist, So a gross income of $5750.