Purchasing a duplex portfolio

[Erik H.]

Recently found a deal offering 14 units ( all happen to be split up into 2 bed 1 bath duplexes).  $650 is the max monthly rent for units of that size.  No unit older that 17 years old no newer than 12.  1100 in prop taxes per unit. Prop manager takes half of first month and 10%. Estimating 5% vacancy.  Thoughts on the max purchase price for this scenario?

Thanks for the input,

Erik