The Price: $559,000

The Property: Revolutionary modernist architects George Fred and William Keck built a lot of low-slung minimalist homes in woodsy environs around Chicago. When it came down to the brothers’ own self-styled dwelling, however, they went with a red brick 3-flat co-op building that can easily stand in for a University of Chicago generating station.

Don’t be fooled by the plain exterior. The Kecks put a ton of finesse and foresight into 5551 South University Avenue, much of it learned from their attention-grabbing “House of Tomorrow” experiment at the 1933 Century of Progress Exposition. In 1937, the Kecks grabbed the top two floors, and never left. U of C professor Louis Gottschalk took the bottom unit, where Arlene Crewdson has lived for 16 years. “[William] Keck’s widow was still on the top floor when my [late] husband and I moved in,” Crewdson told me by phone. Crewdson recently remarried and moved east, creating a rare opening in the building that she hopes will be filled by someone who feels a similar “sense of responsibility to the Kecks.”

With little turnover and loyal caretakers, “almost every original building detail is still here, except in unit two, where the layout was changed a couple of times,” said Crewdson, referring to a period where the middle unit served as a rental and then William Keck’s office. Crewdson’s own space, on the market for $559,000, retains its black-and-white scheme with black tile bedroom flooring, white walls, original wood built-in shelving, and all-white restored bathrooms and kitchen. The kitchen has its original sink and cabinetry. “There’s even an old pull chain exhaust fan,” says Coldwell Banker’s Jennifer Ames, my escort through the property. The hardwood floors running the L-shaped living room/dining room and hallway are newer, but they're no eyesore.

The only real aesthetic obstacle for would-be owners is the exterior metal louver system—it compromises clean views from inside, but gives a nice shifting expression to the building façade. It’s a trade-off not every homeowner would choose.

The finer touches in the Kecks' concept include a central wood-burning fireplace with a brick mantle, glass block windows (also permeating the steel stairwell), and a sizable balcony overlooking a shared backyard. Interestingly, an exit door in one bedroom leads to a rear stairwell. Crewdson speculates the Kecks planned for the possibility of having to split each unit in two under economic hardship. The Depression ended a few years after construction, and such a scenario never came to pass.

The nearly 2,000-square-foot co-op packs in up to five bedrooms, but thanks to fairly even dimensions, it’s a cinch to swap one or two out for an office, den, or library. Unit one is the building’s largest, owing to rear balcony setbacks on floors three and four, but the tight squeeze corridor layout in the back half and nine total rooms compartmentalize the space. That's not a problem for a couple with one or two kids, but a larger family may feel cramped. The units are stacked atop first-floor parking, with the co-op assigning each unit a space.

“It’s the closest thing you can have to a house without the bother,” says Crewdson. Thick concrete walls make for an exceptionally quiet building, all the more important when you’re living opposite a 24-hour college campus. “I’ve always felt very comfortable and satisfied in this home.”

Price Points: Unit one first hit the market with a $690,000 asking price in February 2012, coming down $116,000 by the time the listing was cancelled in November 2013. Coldwell Banker jump-started the listing in late February with a starting price of $559,000. In Ames’ estimation, the prospect of going before a co-op board rattles some shoppers.

Unit two, smaller by one bedroom and 400 square feet, sold in October 2012 for $387,500. Unit three, smaller still, briefly sought $350,000 in 2012 before coming off market.