A friend of ours (we’ll call him Luis) just found his dream car online. It’s a 2013 BMW M-series with only 9,727 miles on the odometer, alpine white, 7-speed auto transmission with a 32-valve, 560-hp, V-8 engine. Mint condition.

With growing excitement, Luis explained that he was saving over $7,000 off the asking price. There was only one hitch. The car was in Los Angeles; Luis lives in south Florida.

We listened as he debated with himself:...