The value of classic cars has gone up by more than 30 percent on average over the last decade, faster than most other investments, placing them among some of the best tax free global investments, according to accountancy firm Blick Rothenberg and auctioneers COYS.

“Classic cars have outstripped most other investments”, said Chris Routledge, managing director of international car auctioneers COYS, “and demand for classic cars as an investment is at an all time high.”

Classic car collectors and investors joined with COYS and London char...