Scrub the doors with Dawn dish soap to clean (you can also use a trisodium phosphate - TSP). Use gloves and eye protection. Spray on the tsp and let it sit for a few minutes, then wipe it off with a clean towel. Use a five in one tool to get the hard-to-reach corners.

Caulk the panel inside corners. Use lightning caulk. Then bondo and prime Nick's and dings.

Sand the bondo and and the rest of the cabinets. Use denatured alcohol and steel wool to prep surfaces you can't sand. Then use a vacuum, air blower, and tack cloth to clean.