Advice on duplex deal -- do it??

[Keegan Darby]

Details: 

Duplex built in 1940. Each unit rents for $600. Window a/c units, there is no central a/c. Self-managed. 

P&I, tax, insurance: $561 

CapEx: $100

Repairs: $100

Vacancy: $60 (5%) 

Water & trash: $55
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$876/month cost

So, $1200 (monthly income) - $876 = $324/month = 324*12 = 3,888

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Down payment: $24k (20%) 

Closing costs: $3k 

= $27k 

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$3,888/$27000 = 14.4% CoC ROI.

Should I do it?