The last thing you want to happen when you're pioneering a new geographic market is to get halfway into it and find out it's a dud. "That's what's liable to happen if you go to the least risky spot first," warns Robert Black, cofounder of $27-million Superwash Inc., in Morrison, Ill. Black should know. Since 1982 he and his wife, Mary, have built 210 car washes and don't have one shaky territory in the country.

The Black method? Identify the biggest problem in a given market. Open up in a location with the highest concentration of that problem. If it works there, the market is golden.

In Oregon, rain was the problem. In Colorado, the problem was a $40,000 water hookup fee and an expensive real-estate market, so Black went into an affluent community and paid the fee. His gamble paid off.

There's still only one Superwash in the Pacific Northwest, but, after his positive experiences in Colorado, Black plans to expand in that market.