This also triggers if high use that there maybe a plumbing issue.

Remove the windows, electrical and plumbing also.

There are issues with electrical, plumbing and HVAC that need attention or will need attention in the near future.  

My uncle hasn't had much trouble finding renters in the past.The property has had a ton of rehab over the last year: new double paned windows, new exterior doors, new A/C and heaters, new plumbing (pex) throughout, new tile flooring throughout, some new electrical (all professionally done and inspected), new bathrooms, new fixtures, 4 of the 6 units have new cabinets, new appliances (stove, refrigerator, no dishwasher), shingled roof (less than 5 years old), new trim added to all the units, new paint both inside and out, had foam insulation added to the attic to help with the heating/cooling as well as protect the new plumbing that they decided to run through the attic, 2 new hot water heaters (each service 3 units), No structural or foundation issues, new water line from meter to the building, and not in a floodplainThe lot is quite big (1 acre) and is zoned commercial.

PL162017Keep plumbing clean and sanitary. (13-196-620 B, 13-196-630 B), (18-29-402.1), (18-29-402.1.1)1st flr.and  1st flr.Bathroom tubs; unsanitary condition.

(Example: If something plumbing not done correctly and I am the one who fixed it, the tenant or whom ever can sue not only my LLC but also myself since I did the work..) 

Plus, it's not a pH neutral product so you are potentially adding something a bit corrosive to your discharge plumbing. 

In adding two bedrooms and converting to a full bath there was obviously some framing, electrical and plumbing work that needed to be done to achieve this. 

Replacement reserve typically breakdown into three groups, mechanical (electrical, plumbing, hvac), structural (stairs, elevators, roofs, windows), foundation ( parking, grounds, sewers).Unit replacements such as carpets, counters, appliances, paint etc..while capital expenditures, are separate from the calculations above. 

Chris White Right off the bat $11K plumbing repair stands out.