First time pursuing a 12 unit apartment

[Robert Wade]

I am looking to buy a 12 unit apt building in a good area that has seven 1 bd and five 2 bd apts.   Current owner has apts at different rents and way under value for a couple.  Rents should be at $450-500 for 1 bd and $550-600 for the 2 bd.  One of the 1 bd is currently renting for $325(long term tenant).  So if I am successful in buying first thing that would happen would be to increase rents to current values.  The building is older but all brick and is well maintained.  I have been able to view 2 of the apts that were empty and they were in good shape(meaning no repairs needed).  Roof is newer.  HVAC: some have been replaced but some may need to be replaced in next few years.  I told her that I would have to view all the apts before we could get serious about negotiations.  For some reason she doesn't want to close on it till in Jan.  She hasn't told me a price but she is thinking it should be worth $575,000 because an apt building next to hers sold for $550,000.  I am thinking around $500,000 would be more in line.   I have an individual that is willing to go in with me and put up the down payment $100,000.  So here are my questions. 1. How would I go about valuing the apts seeing as 7 are 1 bd and 5 are 2 bd to make sure I am being as accurate as can be on an offer? 2. How do I set up terms with the individual to get him a good return and still make a good return myself?     Last  sch C has Insurance at $3947 and Taxes at $2754    Util expenses at $766 (coin operated laundry in building) She is showing a positive income at $24451 on last Sch C.  Thanks for your time.