I'm in no way an expert, we got into it after our friends put theirs up for sale for £600 and we shrugged our shoulders and said "let's give it a go, if it's not for us then we can always sell it and get our money back". We had 2 years out of the van before it leaked too much (it was a 1995 model so that's pretty good going!).
In February this year we decided to have a look for a newer van and spent £6k on a second hand 2007 Swift Accord, 6 berth. That gave us fixed bunks for the boys, so we didn't have to make their beds up each night but also meant we had a side dinette table that they could eat breakfast at.
Buying second hand privately is great as often you'll get loads of "freebies" that the owners no longer want, a dealer would have removed these and flogged them back to you! Thinks like electric hookup cables, water carriers, motor mover (a brilliant bit of kit which gives you a remote control to drive the caravan when it's not connected to the car, great for tight manouvers.), awnings, bins, carpets for the awnings.
We can go away from £8 per night, up to about £35 per night. October half term, 7 nights at Woolacombe is £159 for taking the caravan, or you can stay in one of their apparments for £580, saves a fortune and feels liks home.
We have a mifi loaded with an all you can eat Smarty sim, so netflix, iplayer and access to our media server at home are all accessible!