Audra73:
You say the original factory coating was a powder coating.
Then, some tenants painted over the powder coating with latex paint.
Then you sanded down the latex paint and painted over it with an "enamel" as a temporary fix.
Do you remember if the paint you applied was an oil based paint or a latex paint?
You see, an oil based paint will be durable enough for cabinets. The problem is that whenever you put a strong hard coating over a soft weak coating, then any impact hard enough to break the soft weak coating will result in a "chip" in the strong hard coating above. The strong hard coating on top will stand up well to wear, but not to impacts. Ideally, it would be best to remove all of that old latex paint if possible, because it's the softest weakest link in the chain.
You can remove latex paint from either oil based paint or a powder coating with xylene. Simply get a paper towel wet with xylene (which can be purchased at most paint and hardware stores), and "clean" the cabinets with that paper towel. The xylene will dissolve the latex paint, but neither the oil based paint nor the underlying powder coating.
How well a protective coating performs on a surface depends largely on how hard that coating is. The harder the coating, the less it's going to be scratched or damaged by normal use, like by sliding a heavy stack of hard porcelain dishes or a stainless steel pot over the coating. The less it's damaged by normal use, the longer it stays looking new, and the longer it lasts.
The hardest coating of the bunch would have been the original powder coating. If you painted with an oil based paint as a temporary fix, then that would be the second hardest coating. The latex paint would be the softest coating. Unfortunately, from what I'm understanding, the powder coating is on the bottom, the latex is in the middle, and the "enamel" (which could be anything) is on top, and so the "enamel" paint (if it's oil based) may prevent the easy removal of the latex paint.
If you really like these cabinets and want to keep them a long time, the best conventional coating to have on them would be a powder coating, which are typically about 3 times as hard and durable as "paints". Typically, the cooktop of a stove will be powder coated rather than painted because the heat from the surface elements will soften up a paint to the point that you would damage it sliding a pot onto or off of a surface element. You might want to inquire into the cost of taking the cabinets down, having everything sandblasted off of them, and having the cabinet and doors re-powder coated the way they were originally.
Most of the places listed under "Industrial Coatings" in your yellow pages will powder coat metal. Powder coating is completely different than painting. When they powder coat a metal object, they electrostatically spray a mixture of coloured particles called (pigments) and clear plastic blobs (called resins) onto the metal. Then they bake the metal so that the clear plastic blobs melt and flow together, encasing the coloured pigments in a layer of clear plastic very much like raisins in raisin bread. When that plastic (typically polyester) coating cools, it'll be about 3 times as hard and durable as an oil based paint.
If you really want a durable coating that will last forever, sand blast all of the old coatings off, and have the cabinet and doors nickel plated at any chrome plating shop. Typically, you nickel plates steel before chrome plating it. However, you don't need to chrome plate over the nickel plating. Nickel provides a very hard and durable finish that will literally last forever. Have you ever seen a rusty nickel? No, even the oldest nickels grandpa has in his coin collection are undeteriorated.
That's because nickel, like copper and stainless steel, "rusts". However, the oxide layer it forms is highly impermeable to oxygen and H2O molecules in the air, and so as that oxide layer grows in thickness, it better and better protects the underlying metal from further "rusting". This is why a new copper penny is orange (the colour of copper metal), whereas an old copper penny is brown (the colour of copper oxide). However, the thickness of the brown copper oxide on a 100 year old copper penny is only about twice the thickness as on a 10 year old penny, and that is only about twice as thick as the oxide layer on a 1 year old penny. The rate of growth of the oxide layer progressively becomes slower and slower the thicker it gets because of the relatively low permeability of that oxide film to oxygen atoms and molecules.
Nickel, chromium and stainless steel all "rust" the same way as copper, but their oxide layers are even more impermeable to oxygen, and under normal circumstances never grow so thick as to interfere with light sufficiently to become visible. The coating on a low-e window is typically about 70 silver atoms thick, and you have to have a trained eye to see if glass has a low-e coating on it or not. So, anything less than 70 metal atoms thick is essentially transparent, and the oxide coating on nickel and stainless steel would be thinner than 70 atoms.
I would caution against using a metallic "paint" to get a metallic look on your metal cabinets. Paint simply isn't as hard as metal, and it might look OK when it's new, but it's not going to look like metal once it gets all scratched up from pots and dishes sliding over it's surface. Dirt will become embedded in it's relatively soft surface, and scrubbing it hard enough to remove that surface dirt is going to leave a dull surface, not "metallic" looking at all.
Consider having the cabinets sandblasted and nickel plated to get an extremely durable metal finish that'll be both maintenance free and last forever.
(Then consider getting stainless steel appliances to complement your cabinets.)