There was little plumbing involved (other than a water line for the washer) or structural changes needed (there was a concrete slab already where the patio was).

If the owners can't afford upkeep, they may have major roof, floor, plumbing, electric issues which at today's cost of materials to fix and update will cost so much more than the unit is actually worth.

Looking to find an experienced contractor willing to do work in this area.  

We do see a bit more maintenance in those MF duplexes at they tend to be turn of the century homes with turn of the century issues - shifting foundations, galvanized plumbing, pop fuse electrical, ect. 

Talk to a hundred or so contractors.

Have your contractors buy things local like that.

@Joe Kim  My niche market is refinery contractors. 

I've known multiple people in this area that do BRRRR method but they've always had an in (real estate attorney, contractor, realtor, etc.) in order to hear about the good deals. 

My husband and I are seeking contractor bids to renovate our first buy-and-hold duplex, which was built in 1918 in Norfolk, VA.

She does need some tender love and care, but I'm waiting for a contractor to get out there and tell me exactly what I can do.