@Matthew McCormick its a bitumen (asphalt rolls) roof, has some tear down and aluminum coating already per inspection report seems like seller did that to extend life of roof maybe 5 years ago. 

We had to use 3 coats of Kilz to neutralize the smoke smell, replaced all the carpet, new granite in the kitchen and bath, new appliances and flooring, new fixtures and switches/plugs, and a little drywall work.

I could do four walk-in closets in a day, easy, with the time while I'm waiting for the coats to dry occupied by all the other tasks around the place, even with having to wash down parts of walls and scrub the baseboards, and painting ceiling and trim both. 

You can't sugar coat a property and assume anything in 2021.

Coat metal roof.

The gel coat has to be regularly refinished and fat people can actually break it. 

If the existing trim and doors have a high gloss lacquer coating the painter will likely need to sand and prep all of the woodwork.If you were just painting walls and ceilings and touching up trim I would expect to pay around $3,000, but with the additional $1,400 for ceiling retexturing, and $1,000+ for wallpaper removal and additional labor to sand and prep all woodwork the $6k quote doesn't seem too unreasonable.The only way to know if the quote is high is to get 2 other quotes from other painting contractors for comparison.

@Mohammad Khan there is a big difference between foundation settling issues (foundation is sinking or raising in height) and cosmetic damage to the parge coat, which is what your pics are showing.

Is it in a high end area where the tenants demand granite/quartz and high end flooring, or is a working class area that is happy with a new coat of paint?

You can fix the cracks before you skim coat.