You should remove “Upgrade & Tuning” and “Design & Color”, from the main car menu. That would be a move in the right direction. Later if you ever do it, you could add the Auction House to that menu. It would also make sense to be able to sell our cars in exactly that menu.
In that order:
MY CARS
BUY CARS
SELL CARS
AUCTION HOUSE
Because both of these menu options are available there AFTER you have already chosen a car.
Then “SELL” could also be removed from there. “VERKAUFEN” in german.
Menus shouldn’t be redundant, that is nonsense. Make the menu cleaner, better, with less loading and less steps to take.