Is This 18 Unit A Good Deal?

[Tyson Lee]

I am looking at an 18 unit complex. It consists of two buildings that each have 9 units in them. The buildings have an upper level with units and a lower level with units. There are 12 units that consist of 1 bed/1 bath and 6 units that are studio/1 bath. I have attached rent roll that was sent to me as well as expenses. I could purchase the building for $500,000 and there is possible owner financing but I have not gotten into that yet as I try to analyze the deal. A couple expenses that are not on the sheet are a new roof last year for $11,500 in both buildings as well as $4,000 in paint and supplies. The units are older and could use some updating and the building was built in 1964. 

I currently own a single family that is my primary residence and this building would be my first purchase into rental property. I would love to get insight from others on this deal as well as things I need to look for and be aware of. I'm sure there are numbers that I currently do not have that I need to properly analyze this. 

Any guidance and advice is greatly appreciated. Thank you