Apartment buildings with commercial store fronts

[Jason Smith]

I am interested in purchasing an apartment building as a first investment property, it's the only building that has decent numbers at first glance.   It is an 11 unit building with two store fronts.   Only 4 of the 11 units are occupied at just under 600 each unit per month.   I'm planning on going to see the buildng and ask questions on Monday.  How should I determine the overall value?  Current list price is 159000, taxes are 4300 a year.  Are there any questions other than why are you selling? and what keeps the rest of the building from being rented? That I should ask?   Thanks for your help!  

Newbie Jason Smith