Easy, but can be tricky.
There is a 7 or 8 mm plastic nut on the inside rear of the door panel. Push the door molding out of the way. After removing the screw, start from the rear and moving forward, pop the molding away from the door using a plastic wedge. At the front there is a hook on the end. Push the molding forward (I think it's forward) and it will come off.
It is only tricky when the bolt is rusted and it spins in the molding but won't come out.
1985 Mercedes 500SL Euro (Gray market)
1995 BMW 520i Euro (Gray market)
1992 BMW 525it Wagon
1994 Honda Del Sol Si