I just bought a 2009 BMW 335xi that is Sapphire Black metallic exterior. The car needs to be waxed. I can’t do this myself because of a physical limitation. Is there anyone in the Natick (Metrowest) area of MA that you would trust to hand was a black car and get it right?
Look around for a “Detailer” They should be able to do what you want.
That said, with modern finishes and waxes and polishes, you should not have much of a problem.
Yes take it to a good detailer but will cost you a couple hundred. Just got done with my black one for the Spring and these were my steps: Hand clay bar, power buff with Meg #2 cleaner, power buff with Meg swirl remover, power buff with glaze, hand wax with Meg wax.
You really need to ask them what their steps are and what products they will use. The clay bar treatment makes all the difference in the world in pulling contaminants out and smoothing the finish. At that age a cleaner polish needs to be used, and a glaze under the wax coat will really help produce a showroom shine.
Ask your BMW dealer to recommend a detailer. I had a black car waxed, looked good for 2 weeks, then all the edges where extra wax had accumulated turned white. Not a good look!