Analyzing a Nashville Duplex (help a brother out, *again)

[Kevin Whisler]

Nashville Suburbs Duplex: 

Two 4 Bedroom units that have brand new renovations, HVAC, appliances, etc.

Tenant will pay all utilities.

Principle, Interest, Property Taxes and Home Insurance: $1700

I would be leaving $68,000 in the deal.

Projected rent values are $3900

$100 A month for trash? not sure about that.

Cap Ex 7.5%: $290

Repairs 5%: $195

Vacancy 10%: $390

Property Management 9%: $351

Expenses (Total)- $3026

Monthly cash flow: $874.

Nashville Investors, what am I missing? I know im leaving alot of money in the deal but my cash on cash return is still: $874 x 12 = 10,488/68,000= 15% annual return not including equity.

My cash on cash plus equity is 41.8% 

($18,000 of equity built annually + 10,488 in rental income= 28,488/68,000= 41.8%) 

*I know the capEx and repairs are low but its BRAND NEW*

This is all not including potential appreciation of the Nashville Market.

What am I missing? Someone play devils advocate with me.

*side note: Anyone looking to partner for equity in Nashville market, let me know. Couple of spots left.*