If the paint is in good condition all you really need to do is wash/clay/polish. You may not even need to clay. Put your hand inside a plastic sandwich bag and run it across the paint of the car when clean. If you feel a lot of grit It needs to be clayed. If it’s smooth then you’re just wasting your time with claying.
If you do clay don’t use the old putty style clay as there are lots of new clay gloves or scrubs that make it way easier and way faster.
Then all you need is a good one step polish wax. I highly recommend Meguires D166 or White Wax. These clean the paint, polish away fine swirls and scratches, and leave a nice coat of wax all in one step. I use both and I absolutely love these products. They save me tremendous amounts of time but again, this is if the paint is in decent condition (no heavy oxidation, deep scratches, etc). If the car has been garaged, you will love the results of a one step polish.
Combine it with the green polish pads from Lake Country on a DA polisher such as the Porter Cable XP or even the cheap harbor freight (just buy a new backing plate for it) and you have what you need to make that BMW paint sing.
It does take time though. Even a one step will easily take you 3 to 4 hours when it’s all said and done. So if you don’t have that kind of time and don’t want to invest in the tools just take it to California Auto Buff in Buckhead. If I recall correctly they charge something like $350-$400 for a complete detail inside and out which includes a polish and wax. At that price it will look good, but it won’t be as thorough of a polish as you would likely give it since it’s your baby. Guys I know charge upwards of $750 for a full multi-step paint correction, but the car will look like it did the day it rolled off the factory floor. Better I’d say.
