Not having seriously built a car model for 30+ yrs, I have a question. I'm more accustomed to building armor and ships where finish errors can usually be hidden. Cars are a lot less forgiving, and any small blemish is really glaring. I just want a car model that will please me, but certainly won't be anywhere near competition material. Is there any short-cut to getting a satisfactory finish without spending hours sanding, repainting, and sanding some more? My choice of paints is Tamiya thinned with their own lacquer thinner, airbrushed, of course.

I build open wheel racers before 1970, and classic 1920s and 30s custom body cars in 1/24 or 1/25 scale. I've found the best finishes for car models depend on a dust free modeling environment. Make sure you have a clean, dust free space to paint in. Choose a good primer, and never try and get all the paint on in one heavy coat. This is especially true for gloss paints-- I give the model car body a light mist coat of about 50/50 thinned mix, let it dry thoroughly, and if there are errors, I use fine steel wool (0000 grade or finer) to polish them out, then I rinse the car body in warm water and let it air dry. I apply a second coat, and if necessary repeat the process. I never use fancy sanding or polishing compound techniques modelers sometimes resort to, nor do I use actual lacquer car paint. I find these finishes often come out "over done" so to speak for scale effect. On occasion, if I want a "metal flake" effect, I've used appropriate shades of acrylic nail polish thinned with Tamiya thinner (borrowed from my wife's large collection), but usually my choice of paint is Model Master enamels or Tamiya gloss. Finally, when I have the finish where I want it, I apply a final coat of clear gloss. My favorite clear gloss to date is Alclad gloss-- it goes on smoothly, self levels and leaves a crystal clear thin finish--unlike other gloss coatings, it can even be applied over clear parts . I've also used Future (Pledge with Future now in the States), which gives a similar gloss finish, but it takes longer to dry, requiring you to cover the model in the drying process less some wayward dust gets to the model. In fact though, it's a good idea to cover the model between paint applications anyway, that way no stray dust particles can affect the finish. I use a large inverted clear plastic bin to cover my models during the painting process. I recommend clear, because you can see what's underneath the bin, which will prevent you from inadvertently bumping or disturbing the model while it's sitting there (let's just say I've managed to bang up more than one model under an opaque bin in the past). Hope this helps a little.
VR, Russ

Thanks for the prompt answer. Very helpful. Some of the products you mentioned like Alclad are not available here, but I can use most of your suggestions with substitute products. I should have read the threads under Painting and Finishes first.
But now I have enough info to give it a go.

The best finishes usually just comes from being patient and a clean workspace. Wetsanding for a high quality finish is a must when it comes to cars regardless of what paints you use. For me, I always wash the kit down from any releasing agent during the molding process. Then I sand down the entire body to rough up the surface a bit before primer. Once in primer, I usually let it sit for a few days until the primer is fully dry before I go about my wetsanding. This is the step that is most important to create a smooth surface. I usually go from 320-600-800-1000-1200 before I even get to my base coat. I may go back into primer if I don't create a smooth enough surface. Next up is base coats. Definitely don't try to flood the model as it will appear super think on the body. Multiple light coats is best. Reduce handing time during the paint process and keep it in a contained area to prohibit debris such as dust or dirt to get on the freshly painted model. For clear coats, try to keep the airbrush from spraying too lightly. It will create a flat look and will be extremely tough to get the shine out of the body even with wetsanding and polishing. Don't flood it either, as overrunning clear is a pain in the rear and you will have to wait for it to fully cure before sanding it. In this case, you may not even be able to fix the run either depending on where it is. My biggest suggestion is to definitely take your time. Rushing the paint process is one thing that has ruined many paint jobs in which case I had to strip it all down and restart from the beginning.