You can look around in the forum and you can see a lot of painted laser work.
For example:
Unfortunately there is no powder coated experience I found. Mainly (with the blue laser) the laser burns off the paint, undependendly which coating except clear ones.
This is different if you use the ir-laser, this works on the top surface of coatings, this is also findable in the forum.
By the way, laser engraving is a lot of trail and error, so please share your findings .