Either way the "Caveat Emptor" rule applies but more-so if buying 2nd hand. I purchased my Goldstream 2nd hand and have been happy with my purchase. Even so I was more inclined to a pop-top than a "wind up" camper trailer but like Doug above there was none on the market that suited. My rig does not have the pull-out beds that are more common on these units and I would not have purchased one that did.

In the case of a new unit do your research regarding warranty backup as the answer to your question in this regard very much depends on what van you purchase and where. I'm inclined to think that those manufacturers with a large dealer network would be better in this regard but do your "homework".

Your comment "almost afford one at a push" may suggest you could be over-capitalising if going for a new one. I made the comment recently on another thread that there's no point in buying the van of your dreams if it does not leave enough money to live that dream. In other words there's no point in spending so much on a van that you then can't afford to enjoy using it to the full.

I think the biggest trap in buying second hand is the possibility of hidden water damage. I'm a bit out of my league here so I'll leave it to the experts on the forum to suggest what to look for regarding this.

Have you considered a Motorhome ?

Considered motor home but want to be able to set up camp and have a car to get out and about.
By almost afford it I mean we could manage it and still have savings to help finance the lifestyle! I don't want to spend all my money on a rig and have to go back to work!
The plan is to work three months of any year and spend nine months taking our time moving around Oz.
you know what they say tho... Best laid plans and all that stuff!!

Its a big decision from a lot of different angles... one thing I would like to say is that its never good to spend more than you can comfortably afford... you will end up with less money for travelling and have the constant worry of "What if something goes wrong with the van, or the tug, or your health etc"
Another consideration we hadnt thought of until recently when we got a quote to upgrade our van which at the time was less than 2 years old, is that a caravan doesnt always hold its value even if you've looked after it and its in good condition. Suddenly your big outlay is worth a lot less than you expected. From our experience, a good second-hand one might be a better way to go. But be really thorough in your inspection of it.

Make a list of what you require the caravan to do for you and stick to the plan don't say we will put up if this one because the price sound right , Every time you sell and buy again it cost you money . Take time kept looking till you find what is right for you it took us 6 months to find the layout that suited us , we have had it for 5 years still happy , when looking at caravan imaging living in walk around the bed work out if it's big enough easy to make , dinning set up is comfortable to sit in , can I make a meal in the kitchen have we got plenty of storage hanging space has well . Look at both new and second hand to so you can make the right decision on price if you buy second hand that you don't pay to much . So if you are going to do it get it right the first time so take your time and get it right