Best Upgrades to add value to a commercial building?

[Uke Aliaj]

Hey BP Family, 

I’m very interested in a 7 unit building with 1br 1br for each. 5 of the 7 units are below the average rent market. I want to add as much value to them INSIDE as well as outside… cosmetic and common area changes so I can raise the rents. In regards to inside, what are the BEST materials to use that are tenant friendly and not too expensive. These are units going in the sub $800 a door range. So I do not need ultra luxury, just something that works. 

Thanks for any help!