My Mum and Dad did this on Anglesey when they lived there. they had a garden centre and registered a CL site with the caravan and camping club. 5 caravans and (I think) 15 tents Didn't need planning etc, although all visitors should be members of the caravan and camping club.
They come and have a very informal look around your site once a year, and give you alisting in their book.
They did ok with it, they put in two showers, toilets etc, and eventually hook ups on the field. Even had people there at Christmas one year.
Good luck if you decide to go with it, just a small caution, you will never please everyone, whatever, someone will have a complaint, mum's was mainly children too noisy, but she told everyone it was a family site when they booked, so hey ho!.
Mike