Hi Lisa, when you buy your kit make sure it comes with everything included, if I recall it'll consist of:-
Main leaf spring bar,
car Bracket
caravan braket usually consisting 2 plates,
small screw wheel for the car bracket
snd a locking leaver to put tention on the friction pads
I sold one on ebay a couple of weeks ago as our current van has a hitch head stabiliser on it, you shouldn't have any problems fixing to either your car or van but you will probably need longer bolts to secure the bracket and tow ball onto your car,
I hope this makes sense, it does in my head

)