UK's Caffyns tumbles 10% on first-half loss
** Shares of UK-based car dealer Caffyns CFYN.L down 10.5% at 425p ** Co posts HY underlying loss before tax of 800,000 pounds ($1.06 mln) vs profit of 500,000 pounds a year ago ** HY revenue down 2.7% to 134 mln pounds ** YTD, CFNY stock has risen 5.5% ($1 = 0.7572 pounds) (Reporting by Akshaya V) ((akshayav@thomsonreuters.com))