Primer paints may be oil- or water-based and are used to seal unpainted surfaces to prevent covering coats of paint soaking in. The appropriate type of primer should be used for the surface being painted - wood, metal, plaster or tiles. There are some 'all purpose primers' available which are designed for two or more of these surfaces.
If you have a vinyl top then remove the molding separating the vinyl and paint. Drip rail chrome really should be removed also, but can be extremely hard to take off undamaged. If you plan on buying all new drip molding then definitely remove the old for painting. But if you want to keep the originals then it might be better to leave them on and let the painter mask around. If you have hub caps it's easy to just take them off. While the paint shop should completely mask all four tires, overspray can still find its way in. It's sometimes better to play it safe and just remove wheel covers.
If you are grappling with the problem of choosing a woodwork colour to go with neutral walls, check out Architectural Colours by David Oliver, the founder of Paint & Paper Library. He arranged his off-whites for ceilings, cornices, walls and woodwork in chromatical groups and the concept has been so well received that chromatically arranged colours, such as soft greys, greens and pinks, have been introduced.
Valspar Paint, for instance, also produces paint branded as Laura Ashley, Eddie Bauer, Waverly, and more. These separate lines, or collections, have their own color wheel displays and are usually available wherever the primary brand, Valspar in this case, are sold. Other examples are Disney Paints, currently produced by Behr, and Ralph Lauren and Martha Stewart, formerly produced by Sherwin Williams.
Definitely good inside the house is a new vinyl primer-sealer to be used as a base coat under any paint. It dries in as little as 30 minutes.
For localities where such conditions exist, self-cleaning paints should be selected. These paints are usually so designated on the label. Concrete, plaster, and metal surfaces each present special problems in painting. For instance, paint for use on masonry or new plaster must be resistant to dampness and alkalies, and paints used on steel must have rust-inhibitive properties.
Can you get a good paint job from a low buck paint shop? Yes! Professional paint pros and high dollar restorers may scoff, but it's very possible to get a good looking, long lasting paint job from a discount paint shop like Earl Scheib or Maaco. It's not appropriate for every car. I wouldn't hand them the keys to my Shelby GT500 or '53 Corvette, but for those on a budget it's a very good option. The key to a successful budget paint job is to prep the car yourself. Leave nothing to the shop except actually laying down the paint. (note: For purposes of discussion we'll use a classic Mustang as the example, but this process holds true to really any older car)