so, the time has come for me to paint my car in the next few evenings once i find some free time. ill be spraying a single stage metallic paint, acrylic enamel, jazz blue. my question to all out there that have much much more experience then i do when it comes to this is...after the paint has hardened is it able to be wet sanded and then/or buffed? i assume the latter is doable just by itself with a polisher and some compound. but i have heard mixed reviews as to how or should i say IF you should even be attempting to wetsand single stage METALLIC paint.

I've done a bit of this over the past few years, but I'm far from being an experienced painter...

You definitely have to be very careful wetsanding a metallic finish directly. You can easily introduce variations in how the metallic particles on the surface reflect the light. (You can even have a hard time just shooting it to be consistent.) But, it CAN be done. I would be very light on the sanding, like a very minimal removal with 2000+. And I would try to do it consistently all over, regardless of where it is really needed, just to keep it consistent. I personally would not want to try it on the car first, without trying it out on some test samples because the color and the flake/particle size is also a factor on the outcome. And I probably wouldn't try it at all unless the world ran out of clear coat.

For metallics, I will only do it as 2/3 stage with a clear coat. I have to plan on wet sanding and polishing, as I'm no pro and I can't lay it perfectly from the gun. But if you can shoot well, where you don't need to wetsand, that is also an option.

Looking forward to hearing some other input...

I'm far from a pro myself as well. but base/clear is out of the equation for right now because i HAVE the single stage with all the required hardener, reducer already. the way i see it in the end is a learning experience, and honestly there are only a few more months left in this year for me to DRIVE and enjoy the car, thus the reason I'm just going to shoot it with single stage and hope for the best. as long as its all one color in the end ill be happy, lol. if it turns out THAT horrific, I've got all winter to re-do it because I'm not planning on rebuilding the entire car for a third winter in a row.

You can always clear over top of a single stage and sand/buff the clear. As cbyron mentioned, sanding metallic is not recommended.