If only one area is lower pressure on the cold side, replace the cartridge and blow the line out.

It turned out there were some issues with the shower valve dripping the cartridge.

I contacted the building management company and they mentioned  a pluming company which had done work in other units in the past.That company sent a plumber and it was determined that some of the shower cartridges were failing, so they needed to be replaced.

We have low ceilings and chose ceiling cartridges, but the wall units are much cheaper and easier to install.

My other tenant has a leaking kitchen faucet that leaks from the knob/cartridge and faucet base when turned on but is able to be completely turned off.Thank you!

Could be as simple as replacing the shower head or the cartridge.

@James Louthan I always tell people how great my printer is, when they complain how expensive ink cartridges are.  

I tend to freshen a property up, I do my paint colors so it easy to touch up later, I replace fans with lights, less chance to break, i put in LED Bulbs (maybe overkill) in many cases faucets, and replace shower mixer cartridges, and any obvious damages, Smoke and CO detectors, check furnace and Water heater,  and my standard flooring.

.)- Faucet washers (if equipped)- Faucet cartridge valve (if equipped)?

The only maintenance while she was there included replacing the hot water tank (leak), checking the furnace (gas meter outside froze) and replacing the shower valve cartridge.