Should I buy this Duplex??

[Thomas Brady]

Hey Everybody, 

I am a newbie to the real estate world (although I have probably spent 90% of the last month researching real estate investing, mainly on bigger pockets) 

I am very interested in buying a Duplex and I think I found one that meets all the criteria necessary to have positive cash flow, but I really would like to get some advice from someone that has done this before. 

Here are the numbers on it. 

Asking $270,000 (shooting to get it for 250-260k) Numbers below are for $265,000

each unit is 4 bedrooms, 3 bathrooms, and 2,100 square feet.

Current rent is $1,150 for each unit (however it has not been raised since 2011)

I would say the area is a C class area 

Comps in the area are much closer to the $1,300-$1,450 range for 4/3 

My costs would be: 

Mortgage (PITI) $1,750

Maintenance/Vacancy 20% of rent, so around $550 

I would be the landlord, so that eliminates any management fee. 

Tenants currently pay for all utilities

So the total comes out to $2,300 for my monthly costs

I know I can rent the duplex for at least $2,600-2,700 (some comps as high as $3,000 but I am trying to be conservative) 

That leaves me with at least $300 cash flow/ month, and that would be on the low end of my predictions. 

I just want to make sure there aren't any huge expenses I am failing to see that will kill my cash flow, and if you seasoned investors think it is a good buy?

BTW

I talked to a contractor, and for around 15k I could turn each basement into its own separate unit, making it a fourplex. Basement units could rent for $500-600 and upstairs would be around $950-1100. Like I said, I am new to the game so I don't know how I feel about that route, but it would increase my cashflow by at least $300/month while only increasing my mortgage by about $150. 

Anyway just let me know what you think! 

Thanks