I found the old cast iron waste pipes & the antiquated traps they used were significantly blocked/corroded. 

Some zoning laws are antiquated and you may have zoning regulations that are unfavorable to this type of housing.

Within the first few stays: Cable TV didn't work, there was no water (pump switch was off), and one guest fell through the bed (antique bed with no slats).So, things happen.

Many builder/developers just copy old covenants from other projects that are antiquated and don't apply to the new neighborhood demographics.

The biggest issue is parking as one popular site draws a lot of traffic & the other tenants have to put up signs to reserve a couple of spaces outside their door.Our NNN commercial building, (picked up at auction), has NEVER been vacant & we've had a run of antique auto guys, various contractors & for the last 5 years a young kid who does kitchens & bath remodeling & is booked solid until November 2020.

In fact, it sort of looks like a high-end antique store that was vandalized by an angry raccoon who liked decorating the piles with ladies shoes. 

If you're just interested in clearing the property to get on with the renovation, I would personally call antiques dealers.

Then she wanted 6 names added to the hand built antique mailbox (made by the original old farmer owner).

It looks to be previously used as a storage warehouse, antique store, and recently storage for the owner of the fourplex.

What he discovered is that with no money to pay for heat the tenants were burning his grandmother's antique furniture in the fireplace to stay warm.