Converting warehouse space to apartments in Michigan

[William SaintAmour]

I'm a BRRRR investor with SFRs, but I'm seeing a lot of old buildings built around 1900 that are vacant, structurally sound, already have utilities, and are dirt cheap. I'm seeing these in the small towns that are fringing larger cities such as Lansing, Kalamazoo, etc. On a ballpark estimate, what is the cost to build out loft apartments in this type of space? The roof, foundation, etc. are already good, so it's the interior work that needs done.

Aside from the usual pitfalls of multifamily, any special dangers about this type of project?  The local zoning director is excited about any development, so variances shouldn't be a problem.  Thanks!

And for a background example: 5,000 square foot brick two level picked up for $10/foot.  Empty storefront on lower level and large empty space on the second level.