The Key to successfully painting your kitchen units is the following 4 steps.
1) Degrease Surface with Zinsser Universal degreaser & Paintersworld Wipes. Without doing this first it is likely the paint will not key to the surface, over the years your kitchen will build up lots of grease from cooking. For any painting job it is crucial that the surface is clean.
2) Lightly rub down the surface with very fine sandpaper (P120 or higher). This will improve the adhesion of the primer.
3) Prime Surface with Rust-Oleum Pegaprim Isofix. Unique adhesion primer that keys to surfaces such as previously varnished wood & melamine veneer or any other factory finish.
4) Pegaprim Isofix can be overcoated with virtually any topcoat, water based or solvent based. Providing you use a hardwearing finish such as an oil based eggshell or even a water based like Diamond Eggshell or Isolac Aqua Satin you will be fine.
The following videos show you what process to follow to achieve a great finish in your kitchen at an affordable price.