Airbrush and paint questions

My questions aren't particularly related to car models but I figure what better people to ask, since crusing the forums has already guided me though so many airbrushing questions. Here goes.

I recently got an airbrush kit and decided to use it to paint two cell phone covers a custom color. These cases are metal and I used a Krylon primer and Testers enamel for the paint. After spraying on about 3 coats, I baked them in the over @ 250deg for 1 hours. I must say they turned out very nice looking, but they picked up some surface contaminents along the way. I plan on sanding them out /w some 1200 and then clear coating the cases.

My first question is what kind of clear should I use. After going though the local Hobby Lobby, it seems laquerer is a popular choice. So I picked up a can of model masters flat laquere clear coat, but decided to wait on some input before I spray it. My goal is to have a finish that is as near as durable as something you might buy pre-painted at a store.

My second question is completely unrelated. Another quest of mine it to custom paint a laptop case. The color of choice... hot pink (don't ask... it's for my sister-in-law). Anyway, I know that some laptop manufacturers (alienware, saeger, etc) get their cases in primer brown to start (as you can tell if you've ever taken one apart) and then custom spray them to the color of the moment. I own a saeger laptop and I must say, I'm less than impresses with the paint job they gave it, but to be able to lay down a finish as good as theirs would be acceptable. What should my paint choice be to provide a durable surface?

Thanks alot guys,
Scott