beach worthy bongos!

Anyone else in Bournemouth/Poole? Just wondering if anyone has any tips for making sure sand (which inevitably ends up in the Bongo when you have 3 excited children in the back!) does not ruin the decor? Particularly make sure it does not spoil the runners on the sliding side door!! (we had that problem with a VW camper previously!) But has anyone put extra sheets or mats down successfully? Or any other tips?