48 unit seller willing to carry back 18%

[Luke M.]

48 unit apartment complex located in a C neighborhood. 44 2 bedrooms and 4 1 bedrooms. 3 of the roofs are brand new and one needs to be replaced. 

Common areas of the buildings have been all updated 2014 

seller bought in 2012 for very close to $2.1 and that is what he will sell them to me under contract. 

Loan amount will be $1,722,000 (not exactly sure on the rate yet, finding out) 

seller will carry back $378,000 at 3.5 for 10 years at $3,738 

Rent income/total income   324,060

Expense 

Advertising   $390.00

Insurance $31,200.00

Real Estate Tax 49,440

Repairs & Maintenance 13,312

Utilities 17,236.84 

Total  111,189.03 

Net Income 212870.97 

I am not sure on the vacancy rate. I am meeting with him Thursday to discuss some more details..

Without some main components can I get some thoughts/advice on this deal?