Hello, coming from a door company here I'm sorry but your contractor does not know what he is talking about. You can repaint these doors white no problem! Below is our instructions for painting exterior doors. Honestly if I were you, I would paint all the doors myself, it's not hard and will save you the money.
Paint Instructions - Smooth Fiberglass and Steel Doors
Supplies Required:
High Quality, Exterior Grade Acrylic Latex Paint - Approx. 1 Quart
High Quality, Synthetic Bristle Paint Brush
Painter’s Tape
#400 Grit Sandpaper or green ScPad
Cotton Cloths
Mineral Spirits
Elastomeric or Polyurethane Caulk (To ensure that the door unit is properly caulked and all fastener holes are filled.)
Step #1
Remove or mask off all hardware and weatherstrip prior to painting. The weatherstrip is a friction fit and can be removed by carefully pulling the weatherstrip out of the kerf in the frame.
Note: The door can be removed or left in the frame for final finishing.
Note: Never paint the weatherstrip, the cornerseals or any other vinyl sealing components.
Step #2
Lightly scuff sand the door with #400 grit sandpaper or a green Scotchbrite pad.
Step #3
Wipe the door with a clean cotton cloth dampened with mineral spirits. Allow the door to dry completely.
Step #4
Wipe the primed frame and brickmould with a clean cotton cloth dampened with mineral spirits to remove any dirt or oils deposited during installation. Allow the frame and components to completely dry before proceeding.
Step #5
Apply a quality exterior acrylic latex paint according to manufactures instructions.
Note: Make sure all six sides – front, back, edges, top and bottom – receive the same uniform coverage.
Step #6
Allow the paint to dry completely before unmasking and installing the hardware and weatherstrip.
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Notes on adding color/paint
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