One Sunday in June, a man in his 30s visited the spacious BMW showroom in Tokyo's Shinjuku Ward.

Akio Iio, manager of BMW Tokyo Corp.'s Shinjuku dealership, waited on the first-time customer, showing off the gleaming German luxury and performance cars.

To Iio's surprise, the man not only said he wanted to buy a two-door 650i convertible worth 11 million yen, but promised to pay in cash.