The document linked above contains this very interesting statement:
Second-hand goods
Second–hand goods that you buy from a trader are also covered by the minimum 2-year guarantee. However, goods bought from private individuals or at public auctions are not covered.
In some EU countries, the buyer and seller can agree to a guarantee period of less than 2 years, but no shorter than 1 year. This should be made clear at the time of purchase.
Does that apply to all second hand goods bought from a trader, including motor vehicles? If so, the implications are enormous.