Typically a “new roof” includes removing the old roof. For example in 2019, our experience of removing one roof system and installing another on a house varied from $5,000 to $88,000. To drill down further, our prices ranged from around $275/square (square = 100 square feet of roof surface) to $450/square.
Designer shingles are more expensive than architectural laminates and the laminates are more expensive than the three-tab shingles. The steepness of the roof slope, size of the roof, what other components are used in the system, warranties, complicated rooflines, access to the house and attic ventilation systems and more, all contribute to the cost of a new roof.
NOTE: The square footage of your house is not the same as the square footage of your roof. Depending on the steepness of the roof slope, the width of the eves, roof coverage over porches or garages not counted in your house size will greatly increase the square foot size of your roof over the square foot size of your home.