I want to paint just the trim (baseboards, etc.) in my kitchen. What kind of paint do I get? A clerk told me to use "Kilz" – but there’s a bazillion different ones! The result I want is shiny and I only want to have to use one coat, so it should be thick. What do I ask for?
Also, should I "roughen up" the surface with sandpaper? (I’m painting over the same color) – do I have to do anything else first, during, or after?
What is TSP?
Clean well with TSP, two tablespoons per gallon. Rinse well with water and dry thoroughly. Clean a small area first, if the result is glossy then sand with a fine grit paper before cleaning.
Unless the existing paint is an older oil base, I would use a latex semi-gloss trim paint. Avoid really cheap paint, I would expect to pay $20 – $25 per gallon for a good paint. Not all paints in this range are good, but the ones that are much less expensive are usually not so good. Since you are covering a similar color, one coat should not be a problem with any good paint.
If you really want a high gloss, you could use a high gloss acrylic, same directions. It may require two coats as a good gloss acrylic is usually thinner, even in the best paint.
Contrary to popular belief, priming in this case is not a good thing. Primer is formulated to grip onto and seal porous surfaces such as bare wood. A surface that has already been painted is already sealed and does not provide a proper surface for use of a primer. The result can be peeling or bubbling paint (not always). If the surface to be painted is stained with a bleeding stain such as water or smoke damage, a stain block is fine, not a standard primer. Stain block may also be helpful if you are covering a contrasting color.
Oops, forgot, sorry. TSP is Tri-Sodium Phosphate, a heavy duty detergent. Available most places that sell paint, usually in a 1 pound box.