The property in the midst of an older industrial estate looks more like a car graveyard than a collection's home. Behind the wire fence rest a good dozen incognito casualties, protected against weather by yellow covers or gray tarp. Behind the gate, however, a tightly packed array of shining BMWs from the '60s and '70s await us in what is half warehouse, half workshop. When he ran out of floor space, 48-year-old Rey (last name withheld on request) started stacking the surplus stock on hoists.

Right now the head count is 52, but it fluctuates as this makeshift enterprise seems to buy and sell cars on a whim. "I once had 14 2002tii models in various stages from neglect to perfection," recalls the former football player who made a small fortune as a broker in the dairy business. "Presently, I'm down to three. I also have three carburetor-fed 2002ti models, which I actually prefer to drive. They are that bit more responsive." He rotates regularly through his treasures, taking each vehicle for a spin or a longer journey about three times a year. Favorites? "As far as modern cars go, the M2. From more recent times, the 3.0 CSL and the E30 M3. Out of the older stuff, I love the 02 series and Neue Klasse from the base 1600 to the up-market 2000tilux."

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Four experts manage this place: Michael, a retired German racing school instructor and M1-homologation specialist; the local mechanics Dave and Jason; and Rizzo the Prague ratter. The what? Just a few pounds of guard dog, which allegedly owes its name to the medieval keepers of Prague's Hradschin Palace, kept rodent-free by a squadron of these big-eyed, shark-toothed rat catchers.

Rey buys some of his toys in bulk and others individually, sometimes merely to save a rarity from the shredder. Among the patients awaiting treatment are a rusty 2000C coupe, a half-finished Malaga Red 2002ti, and a U.S.-market-only L6 with front-end damage. Unlike most classic car buffs, Rey does not necessarily insist on originality. "I own several Alpinas that, strictly speaking, aren't originals," he says. "And I do like crazy one-offs like the wild, wide-body 345i powered by a 745i motor, the stealth 2000 saloon equipped with a later-day 2.2-liter M3 unit, or the rear-engined lightweight 700RS roadster of which only two have survived."

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In addition to nine Alpinas, he owns an interesting fleet of high-performance models. Among them: 15 ti and tii models, the aforementioned CSL, and a bunch of early M3, M5, and M6 models. Having started his collection in 1992, he is still chasing a number of cars, among them the ballsy 1800tisa (only 200 were made), an M1 project car, and a 2002 turbo that doesn't need an awful lot of work. "Trouble is, to make a small fortune on classic cars requires a big fortune to start with," he chortles. "So I'm constantly looking for relatively affordable sleepers like certain limited-edition models, rare color and trim combinations, and older stuff such as the 502 Baroque Angel or a 3200CS Bertone."

Money being no object, what else would he buy? "Any two-door 502 would be nice to have, also a 503 coupe, and of course the out-of-reach 507," he says. "I also fancy something older, like a 327 or 328, both in open- and closed-top form." How about a Z8 or an i8? "Nice, for sure. But too modern, too difficult for us to work on."