when my son was born i had an excuse to get a new car, i pick it up base on price, fuel consumption and boot size
the winner was the skoda superb greenline (wagon)
permanently inside the boot, not visible from the outside:
1 skim board
1 TT with boots on
3 or 4 kites
harness, wetsuit, etc
as my missus use to say - ´you did bought a car for the family, but the kite family - the 7, the 10, the 11, the 13..."