The mood in the home building industry is officially glum. Buyers are playing a waiting game, and inventory isn't moving. Except in the case of that builder around the corner whose homes are being snapped up faster than free NFL tickets on Craig's List. What gives? A side-by-side comparison shows him selling the same square footage with the same amenities at the same price point you are. He paid the same for land and water taps, and he uses comparable subs. And yet his houses have a certain allure that buyers can't get enough of. He must have invested a fortune on something that's making them bite.

Then again, maybe he didn't. Sometimes the tiniest design details—extras that cost pennies on the dollar, or simply require a little sweat equity and nothing more—can make a big difference in the way a house lives. BUILDER consulted a handful of industry veterans targeting middle-income buyers (folks accustomed to balancing price with cachet) and asked for their most cost-effective design secrets.

TRICKED OUTTRIM If you've written off handsome millwork as a luxury reserved for pricier houses, you may be cheating yourself out of a sale. Take it from Steve Kendrick, owner of Structures Building Co. in Mount Pleasant, S.C., where paneled wainscoting is as much a part of the local flavor as roadside barbecue. To save on costs while honoring tradition, Kendrick has created a pared down version of the real thing that looks great. He uses 1-foot-by-4-foot strips to add dimension to plain walls, but the expanses between those stiles and rails are drywall, not plywood.

“We paint that part of the drywall with the same oil-based gloss paint as the wood trim, so it looks like wood paneling,” says Kendrick, who builds roughly a dozen houses each year, half of them on spec. “It doesn't matter whether the chair rail begins 2 feet or 6 feet up from the floor; we're still using virtually the same amount of trim.” As a finish, the horizontal rail is topped off with a strip of poplar bed molding. Other times, Kendrick mixes things up and simulates a beadboard look by scoring a sheet of birch plywood with a router and then painting it with the same gloss paint—at a third of the cost of real tongue-and-groove beadboard.

Structures has also won points with buyers by wrapping its bathroom mirrors to look like built-ins. “Instead of just slapping up a plate-glass mirror and leaving the edges raw, we'll wrap it in the same trim, sill, and apron material we use on the windows. This creates an inset so you can mount lighting on top of the mirror,” says Kendrick. “This is something we do a lot in powder rooms, which get a lot of foot traffic from guests, not to mention visitors touring our spec homes. In the low-country cottage style, it's a detail people like.”

STUFF THE ENVELOPE You've maxed out every inch of the floor plan, but have you considered how to take advantage of unused volume space? If you really want to push the building envelope, think about it in 3-D. Consider tucking an intimate reading nook into the dead space under the stairs, putting built-in shelving at the end of a hallway, or carving a functional loft into the attic roof structure. The latter is something that can be done with traditional framing and a standard truss package, “at a fraction of what it would cost to bump the house up another full story,” says Ed Binkley, national design director for the architecture firm BSB Design.

Closets and laundry rooms are additional sweet spots that often get overlooked, Binkley says. “If you have 10-foot ceilings in your house, but you only need a 7-foot ceiling in the closet, that's 3 extra feet of volume space that often go unused.” In a kid's room, that's prime real estate for a secret hideaway with a ladder going up to it. In a master suite, it could serve as a bonus storage area for seasonal clothing.

Thinking in sections has become standard practice for builders working in areas where land is scarce and small footprints require a more vertical mentality. SummerHill Homes, which builds on small lots in and around Silicon Valley in California, reassesses the potential of every nook and cranny and how those spaces might be exploited to serve home buyer needs. “People need space to store their holiday ornaments, photo collections, and suitcases,” says Tad Holland, vice president of marketing for the Palo Alto, Calif.–based builder. “In smaller homes this is a big challenge. If we have a 20-by-20-foot garage with an up-slope in the front, we'll leave that space open for storage instead of covering it with [drywall]. It might cost an additional $100 in electrical wiring to put a light fixture in that storage area, but what home buyers gain is significant.”

Learn more about markets featured in this article: Portland, OR, Denver, CO, San Jose, CA, San Francisco, CA.