Nobody wants to guess so we move to another building. One which has been gathering dust on a shelf for a few years. A Belgian customs building based on the real thing  at Macquenoise, Belgian-French border, coordinates 49°58'32.12" N   4°10'43.03" O if you are interested . It's been out of business for more than 2 decades but was temporarely refurbished for the movie "Rien à Déclarer" in 2010.

In reality you wouldn't find any trilingual signs but you can use those delivered with my customs guard house too.

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