Anyways,

I just picked up an E550 Coupe with a couple hundred miles at the dealer, so I am wondering, Would the shop remove the dealer installed wax, or should I do it myself?

Basically, I am wondering if there is any "Self prep. work".

Thanks, I appreciate it, especially if you are a professional..

-Alex

They'll likely use an isopropyl alcohol wash, which you should do as well because you will want to inspect to make sure the surface is polished correctly.

why would you presume the dealer ever waxed the car to begin with?

Dealers will wash cars but waxing new cars is not the norm.
A customer can request a new car be detailed as part of the sales agreement.
Waxing a car is an unnecessary operational cost that is avoided
Many dealerships have car washes on or near the premises.
These car washes are automatic, These are typically used for customer cars being serviced.
New cars are not typically waxed.
Nor are they ran through the automatic car wash.
Wax turns white on vinyle, leaves debris, and buffing causes swirls.
An automatic car wash can leave scratches in the paint.
There is a good chance that any new car that you buy would have only been washed once, and that would be after it was sold to you.
No one is going to expect to find wax residue and swirl marks on a new car.
New car paint can be contaminated with oil film and exhaust film
A good cleaning with soap and water is the safest basic prep work you can do.