Hey @Dominick Fiordimalva, i've been looking in Troy for the past 6 months now and actually got a place under contract on 4th street but slightly further north (it fell through due to structural problems not worth fixing). The area you're looking at is priced at $45k for a reason. It's a tough area and can have some difficult tenants. I mention the deal i had under contract because after it fell through, the owners had to start the eviction process on tenants they signed just 4 months earlier. that's not to say there's not opportunity there but you should expect challenges and factor accordingly.
A couple thoughts on your numbers... your taxes are low, they're closer to $5k, In Troy you can get the Tax Roll from the city website to see what the taxes are in 2016 and you can also look up the school tax. Also i don't think $5k is a very conservative number on M&R, even if you're including CapEx, which i assume you are. you're probably going to have more repairs to do with lower quality tenants and older homes, potential eviction costs and CapEx will cost the same whether it's a $45k duplex or a $150k duplex, beware of using percentages. i would use at least $6k for conservative numbers and i would say it's closer to a 9.5% cap rate.
i also wouldn't trust a 3 bedroom and 2 bedroom getting the same rent until i saw the leases myself.