Before you book any UK holiday park, a handful of straightforward questions can save you from an awkward surprise on arrival.
If you're travelling with children, pack a beach bag that stays by the door, buckets and spades, a windbreak if you have one, sun cream regardless of the forecast, and a full change of clothes kept in the car rather than the caravan, since sandy, wet children rarely want to walk back for it. Bikes are worth bringing if your park has cycle paths or is close to a coastal trail, and a car boot cool bag makes packed lunches for day trips much easier.
Ground floor access matters more here than on a standard family trip. If grandparents are less keen on stairs,
https://www.tripadvisor.com/Hotel_Review-g528807-d17635106-Reviews-South_Shore_Holiday_Village-Bridlington_East_Riding_of_Yorkshire_England.html check unit layouts before booking rather than after, since not every caravan or lodge is single-level, and a quick question to the park before you book saves any awkwardness on arrival.
Getting three generations away together takes a bit more planning than a standard family trip, but a holiday park set-up handles it better than most people expect.
Timing affects cost as much as accommodation type. Travelling outside school holidays and bank holiday weekends, even by a few days either side, tends to bring costs down considerably, simply because you're avoiding the weeks everyone else is trying to book. If your circumstances allow any flexibility on dates, this is worth more than almost any other single budgeting decision.
A spontaneous short break is entirely possible with a UK holiday park, you just need to know where the flexibility usually sits.