That seems to be a good idea Ric.ror.....it will provide you with holidays for many years !
But choose your site carefully. Most sites are only open 10 months of the year. Mine used to be open until Jan 6, so I was able to spend Xmas and New Year there, which I loved. But not now.
Once you have the 'van, you will find yourselves using it much more than you thought. Stay in a rented 'van, on the site of your choice first, and see if its the correct one for you.
Personally, I don't like too many people and an on-site Club is definitely not my kind of thing, but it may be different for you. Also, perhaps choose a site that is within a reasonable travelling distance from your home, so you can pop down for the weekend, at a moments notice. Mine is in Cornwall, which I dearly love but its about 4 hours drive away.