Need help with property value

[Jeremy Hartwig]

I'm looking to purchase an 8 unit property.  The owner is asking 600k but I'm not sure his valuation is accurate. The property consists of two 3 unit and one 2 unit buildings.  All units are 2 bed 1 bath, single story with off street parking.  He is currently getting $550/month for each unit.  I believe that when determining value in commercial real estate part is based on current rent.  If I'm wrong I'm sure someone will correct me.  If someone can explain or point me in a direction that could help with that that would be great!