Like the saying goes… Time, Cost, Quality and one can pick two!
When it comes to remodeling my tendency is to sacrifice on time. The range is typically the costs involved for almost turning the interiors brand new by purchasing products off the shelf from HD/Lowes/Costco/Amazon/…. without any professional discounts. The costs does include materials and hired labor. What it does not include is the time spent by one, and possibly any expensive tools purchased for the diy remodel.
As for painting, that is one of my favorite aspects of remodeling so am not certain about the labor costs to paint the house professionally.
2) if the faux painting is just a mix of dark high gloss paint then the repair might be simpler. Clean the walls with TSP solution to remove the dirt and
grease. Finally prime and paint.
As for painting (a) 1 or 2 coats of Zinsser bullseye interior/exterior primer followed by (b) 2 coats of Behr Semi-gloss Paint in Kitchen & Baths (or) 2 coats of Behr Statin Paint in rest of the house.
The paint +supplies cost about 1.5K, but it is worth the expense and efforts. The statin/semi-gloss finish do not show dirt/finger prints, and can be easily cleaned with mild soap and water.