First reaction was to sell the top 2 to your local Citroen and Audi dealers.
Then I tried to be sensible. Quite hard. But I tried.
What's to stop you putting on your own exhibition? Get a local hotel to display them for a few weeks in their foyer?
If you bought your MB from a main dealer, get the dealer to exhibit them on one of their open evenings.
If a % goes to a popular local charity you might find the hotel/dealership/whatever quite receptive, and the local paper will love a feature "local artist raises money for hospice" or whatever.
Ebay? "art originals"
Must stop being sensible now... my head is starting to hurt.
There's a fine line between a denominator and a numerator.