If it’s just the electric then either pay that units electric yourself or add a common area panel/meter.

Add solar panel.

I’ve also had issues regarding aluminum wiring, electric panel not being up to code, rotted wood from a ton of moisture, and foundation issues.

Some people say, there is a stamp under the kitchen sink or electrical panel.

No replacement panel will ever make it attractive. 

My smallest project which did NOT need any HVAC, siding, roof, panel upgrade, just small cosmetic job was about $30/SF, with me doing a bunch of the work.

"ok, this is the hot water tank... these are glass block windows... here is the breaker panel... it was crazy. 

@Allison C HendersonWhy not find four 6” circular access panel covers and cover the holes?

That said, there's about $5-6k in roofing, both bathrooms, both floor kitchen appliances that need to be replaced, electric panel needs to be converted from fuse box to circuit breakers and the upstairs furnace seems to be on its last leg.I don't think I have enough to do all the rehab at once, and the roof seems to be holding for now.

He drives by each property on the 1st of the month and the tenant has the check taped in the electric main panel box.