Avoid Campbells Caravans

We went into Campbells caravans;s in Lostock Hall to look for a newer caravan, we saw one we liked and put a deposit on it, they gave us a price of £4,000 against our caravan, which, I admit they hadnt seen, we arranged to take our caravan in for a appraisal and the offer was dropped to £3,500, because they said there was a damp reading of 35% under one of the windows. Which I might add we new nothing about, we were gutted as we were convinced our van was 100% dry or as near as is possible.
We decided we would reconsider and pulled out of the deal.
We then saw another caravan at the Kirkham branch and explained fully what had happened and that we had the window rubber replaced to cure the water ingress and was told by an authorised repairer that the board would dry out and problem solved, it wasnt necessary to replace the board as the problem was very minor. We explained everything and the sales man agreed but asked if he may concur our story with the salesman at the Lostock Hall branch and he confirmed fully what we had said.
We then say another caravan we liked so entered the process again, we arranged to take the caravan in to swap with a difference of £3500. To which we agreed. The salesman said he would accept the appraisal which had taken place at Lostock Hall and everything was all systems go. We took the caravan in to bring our new one home only to be told the caravan was more damp than they thought and the reading was now 95%, this is within 3 weeks, after the repair and some of the hottest weather we have ever had in the UK, and now they wanted another £700 pounds to swap on top of the £3500 already agreed. I was absolutely livid, as they completely went back on our agreement.
Not only did they do it to us they did the same thing to an older couple who were in front of us as well, only they decided to pay.
Do not deal with this so called reputable company, they had no intention of honoring this deal, CAMPBELLS CARAVANS ARE DISHONEST AND IMMORAL.