Have had caravans and now a Motorhome (7.5m) for over 30 years and always kept on driveway. I believe there is a restriction in the deeds about caravans somewhere but no-one seems to take any notice. As long as neighbours don’t kick off its fine. Also very handy for keeping batteries charged and putting an oil-filled radiator inside during very cold spells. In addition, my exterior home security cameras and lockable steel pole in the driveway help reduce insurance costs!