What is the going price for painting 1100 square feet of walls height 12ft 800 square feet of ceilings lowest height 9 feet highest 15 feet sloped

What is the average cost to paint home interior walls by professionals per square foot. 1 coat and 2 coats. One color and two colors.

I have been approached about painting the interior of someone's house. What is a fair price for 1100 sq ft with vaulted ceilings of 15 ft? This will include trim work, mantle and columns. I will have to move furniture and do some prep work.

Does painting an interior wall with two coats of paint instead of only one change the color. For example, does it make the wall color darker, deeper, etc. If the wall color is brighter than you expected, will two coats of paint darken the color a little? Or are you just stuck picking another...