Do anyone know where to buy Roof boxes for the car. I see people with them, but not seen in the shops.

Looking for at least 400L sized one for a Chrysler Grand Voyager (Town & Country)

I saw them during the month of August at Auchan when they had all the big sales for the Summer Holiday. I can't remember if they still have them for sale or not though. Carrefour might be another good place to look since they are similar to Auchan, too. Sorry I couldn't be of more help.