I've thought about installing a hitch for a bicycle rack, but... is pulling a trailer good for a 300E, especially a smaller-engine/tranny one?
I'd look into renting a small truck and either drive your car separately or tow it behind the truck like this:
Now that's a happy car! Not sure how that'd compare to the cost of a hitch + trailer rental, but you also save real money in wear on your car.