Duplex on Concrete Slab, add HVAC or no?

[Medriand Arnold]

Hello BP, I am currently looking at obtaining my first property. The property is a duplex I am still working on, but there was something that struck me. Both units have window unit A/C. The house has never had HVAC and is on a concrete slab. I was wondering would adding HVAC be worth it. The house is worth about 140k ARV and rents are 850 around it. Current rent is 650. Both units are 2/1. The property is in Upstate, SC. Any help would be wonderful. Thank you.

[Laurie Clarkston]

I am renovating an old (church) building into 4 units - 2 up and 2 down.  I am installing HVAC into all 4 and the quotes I got for all units together was $18,500 - 20,000 ( or about $5000/unit including units and ductwork for 1300-1400 sf each)   They are running all of the ductwork through the rafters upstairs and in the basement apartments - I assume they will install in the ceiling somehow - They will not have to do anything to the slab (I know because I just spent a ton to replace the sewer line and put water, plumbing, and electric for the islands into the slab.)  So I don't know how the slab would adversely affect anything.