195 Unit High Rise Concerns

[Spencer Gray]

I'm looking at 195/unit property in Indianapolis consisting of two 9 story connected buildings built in 1951. Roofs, windows and central water heating have all been replaced within 5 years, but the central gas fired boiler may be the original. I've never looked at property like this and am curious what concerns I should keep in mind. My biggest concern is replacing the boiler which I will assume I will have to do at some point (or a major overhaul).

There are a number of concerns that are obvious like owner paid utilities, window AC units, but are there any other major red flags in high rise buildings that I should be aware of? 

Thanks for your help!