When we used to visit family in Henfield in the 80's / 90's we used to drive in down Devils Dyke, passing a windmill or 2 and park relatively near the pier for either free or next to nothing...
Last year we drove in for the day and paid £25.10 for 4hrs in a car park just behind the sea front. I was going to reverse out when I saw the parking tariff but someone got behind me!