Hey mate,
i assume you are in Kuala Lumpur so the locations of the places im about to mention are located in this area.
For maintenance, checkups and repairs you should try "M1" located in Segambut. My parents have sent their BMWs there for the passed 15 years for maintenance and repairs. They have done a very good job making sure our cars are running in top condition.
For your OEM bodykits you might want to try "sportline" located near Sunway Lagoon. They have a wide selection of bmw parts for the E38 but can be a little pricy. Unfortunatly for you im not in the country so i wont be able to take you there and introduce you to the guy who owns the place. His prices can be very resonable but ill see what i can do to get hold of the guy who runs the place.
If seen other members talk about places where you can get your car detailed so you might want to look around.