Most BMW E34s came with the standard chrome trim around the door windows. The M5 and maybe some other trims (540?) came with a shadow line option, which is a matte black finish instead of the chrome.
To purchase the factory matte black trim, the cost is over $500. Many people paint their chrome trim with matte black paint. I found shadowlinetrim.com by chance, which is a vinyl wrap, so I decided to give it a try. It appeared to be more durable than the paint, and a lot cheaper than buying trim. One roll of 3" x 30' vinyl is about $30, and is enough to do the car.