Or selling to another trader - they are considered to be experts and don't need the same protection as offered to consumers.

I bought a wee car off one of my dealers for my sister when she passed her test. They had taken it in as a part-ex, but it was a rebuilt write-off so they couldn't/wouldn't retail it but, because I worked with them in the industry they sold it to me on an invoice marked TRADE SALE in big letters top and bottom. They couldn't do that if I was a walk-in customer and it is probably arguable that they shouldn't have done it for me either. The car ran perfectly for years, by the way.