"Der Experte" or "Non Stop Trouble with the Experts" is a West German German-language film from 1988, so this one will soon have its 30th anniversary. It is one of the later works from German actor Didi Hallervorden's very prolific 1980s in terms of German comedy films.
Though never subtle this Dieter Hallervorden vehicle does not have the tastelessness of some of his other films, and certainly the first half is entertaining and funny (a little knowledge about German politics is required here). But the satire dies out and the story switches to a too sentimental story with Dieter trying to get back his young friend Paul.