How do I paint vinyl kitchen cupboards?

You will need to get a bonding primer to use before you paint the cabinets. We painted our cabinets and it was one of the best and inexpensive projects to date.

https://www.cribbsstyle.com/how-to-paint-cabinets-not-just-for-your-kitchen/

How to Paint Cabinets

Make sure they are clean and dry. Remove the doors and hardware. Mark the doors and cabinets with tape where they go. Lightly sand the doors and cabinets to remove any gloss and roughen the surface for paint with 100 grit sandpaper or a green Scotch Brite pad.. Use a tack cloth or damp rag to remove dust after sanding. Prime with a stain blocking primer like KILZ. Acrylic or water base paints are low-fume and clean up easily with water. Alkyd or oil-based paints require good ventilation because the paint contains solvents that can irritate your lungs and make you feel sick. Alkyd options require mineral spirits for cleanup, but they provide a hard, durable paint finish. Whichever you use, buy the best-quality paint you can afford for a lasting kitchen cabinet finish. Seal with at least three coats with a water based polyurethane. Use a small foam roller and foam brush for a smooth finish.

How to Paint Cabinets

Make sure they are clean and dry. Remove the doors and hardware. Mark the doors and cabinets with tape where they go. Lightly sand the doors and cabinets to remove any gloss and roughen the surface for paint with 220-grit sandpaper. Use a tack cloth or damp rag to remove dust after sanding. Prime with a stain blocking primer like KILZ. Acrylic, or water-base, paints are low-fume and clean up easily with water. Alkyd, or oil-base, paints require good ventilation because the paint contains solvents that can irritate your lungs and make you feel sick. Alkyd options require mineral spirits for cleanup, but they provide a hard, durable paint finish. Whichever you use, buy the best-quality paint you can afford for a lasting kitchen cabinet finish. Seal with at least three coats with a water based polyurethane. Use a small foam roller and foam brush for a smooth finish.

Could you remove the vinyl with a hot air gun then. It takes a while but it does peel off the vinyl then sand and repaint the wood or recover on top with another vinyl maybe

If the vinyl isn’t peeling, you could try painting it with milk paint. Milk paint is made to stick to surfaces with only minimal prep work (Hand sanding and cleaning.) I painted my oak cabinets with General Finishes Milk Paint, Antique White and they look great! You can see my cabinets here: http://momhomeguide.com/my-painted-kitchen-cabinets-a-year-later/ Good luck!