Drive far enough down Rainier Avenue South and you're likely to pass an example of one of the Valley's cooler phenomena: the business that is home to a second, dissimilar business. It's a relatively recent innovation, designed to maximize the spending potential of customers whose transactions require an extended stay. As such, there are furniture stores that double as Asian barbecue joints, car dealerships that sell espresso, and an auto-parts emporium where one can pick up a case of Miller High Life.The granddaddy of these hybrid enterprises might be Auto Fitness. For the past 20 years, Robert Washington's hand car wash and detail shop has been a south Seattle mainstay. But it wasn't until a decade after he opened that Washington hit upon the idea of retrofitting a portion of the shop as a restaurant. Thus, Grubz Grill was born.But good ideas beget competitors, and Washington now has two nearby—one of whom is his former wife. Located just north of Auto Fitness, Maria Washington's Auto Care Detail is part deluxe car wash, part clothing store, and part used-car dealership. The cost of a wash and wax—rims included—averages $70. But during happy hour (5:30–7:30), barbecue sandwiches are free.Maria opened her business in July after a stint in Virginia Beach, Va. She and Robert remain cordial, she says, but she doesn't mind becoming the competition. And like her ex-husband's business, Washington's car salon consists of a large parking lot with a collection of small buildings in the center, one of which is a clothing store. Each morning she hangs a row of tall white T-shirts on the gates outside, all of them emblazoned with images of Michael Jackson and other screen-prints of the moment. The shirts haven't caught on yet, she says, but help to attract business—especially on weekdays, when, Maria says, "Sometimes you'll get chicken, sometimes you'll get feathers, but you have to do whatever it takes to get those cars in here."Up the block, David Dumas faces the same imperative. He can be easy to miss, sitting in a plastic lawn chair outside the gates of a small strip of businesses where he rents space. So he whistles, yells—whatever it takes to catch the attention of cars waiting in traffic on Rainier Avenue. Sometimes the tactic works. On one recent day, however, Dumas, 52, has yet to attract a customer. At $15 per car, his price is comparable to the two other hand car washes on this section of Rainier. But unlike the Washingtons, Dumas' He-Man Car Wash is somewhat dependent upon his fellow tenants for customers. At dusk, both the neighboring electronic-equipment boutique and recording studio are empty.Still, Dumas hopes to open two more locations before the year ends. "There's enough money out here for everyone," he says, before whistling at a passing car.