Sure, they had all seen the model units of the high-rise before they bought their own, a decorator’s idea of modern, urban living with straight-edged white couches and pops of color — and not a soul living in them.

But once they moved in, how did these new urban dwellers decorate their own spaces? And more important for the voyeur in all of them, how did their neighbors decorate theirs, especially the guys in the penthouse?

Last week, homeowners in the 22-story “The 88″ on Second Street in downtown San Jose hosted their own “progressive design party” to show off their own places and peek in on others.

“I want to see how other people live,” says Karen Mandell, who had cheese and wine waiting for her guests in the unit she shares with her husband on the ninth floor. (Hint: There was more than one white couch on the tour.)

High-rise living is new to San Jose, a city known more for its suburban sprawl than hip downtown living. Beginning in 2007, just as the real estate market was tanking, the first of four towers were built downtown, starting with City Heights, then Axis and The 88 and finally the 360 Residences. The 88 is the tallest of the four. It opened in late 2009, is 65 percent full, and the homeowners couldn’t seem happier.

About 30 neighbors gathered first in the “entertainment room” on the fifth floor that opens to the spalike pool and grand, tree-studded terrace. And a surprising mix of neighbors it was, from European singles working in local high-tech to a young couple who traded a 3,000-square-foot in Denver, to empty nesters who left their Redwood City home of 33 years.

The Colorado couple are Karen and Evan Mandell. They moved to San Jose in late 2009 when Karen Mandell, 37, got a job as the research director for the Mineta Transportation Institute. She gave up her car when she moved here and walks the half-mile to work.

“It’s a very simple, clean, sustainable lifestyle,” she says. (Grocery shopping is easy with a Safeway on the ground floor, her husband says. “It’s like having the world’s largest refrigerator in the basement.”)

When they sold their big Denver home and were moving to the one-bedroom unit in the high-rise, they were faced with the quandary of what to do with all their heavily carved, marble-topped Baroque-style furniture. “We sold everything but the bar,” she says.

“You have to maximize your style when you only have two or three rooms to work with,” Evan Mandell, 38, says.

In came a new white leather sectional, a triangle-shaped dining table that seats six and a can of dark red paint to add drama to the living room walls.

While Karen Mandell gave up a lot of furniture, she didn’t seem to get rid of any shoes. She has floor-to-ceiling shelves of them in her closet, which she illuminated with a pink crystal chandelier; it was one of the most popular rooms on the tour. “Who are you, Lady Gaga?” her neighbor, Rosa Passanisi, asks, peeking in.

Passanisi, who works at the U.S. Postal Service with her husband and is nearing retirement, took a different approach to decorating. She simply moved all the furniture that would fit from their Redwood City home, right down to the oak ladder-back dining room chairs. Her house is comfortable, she says. “We don’t have a showcase house.”

Mohamed “Mo” Marleen’s 14th-floor space couldn’t be more modern, from the white couch to the bubblelike chandelier and arching globe light.

Rob and Laurie Howe moved much of their traditional furniture with an Asian influence into their 17th-floor home, adding walls of storage to accommodate the extras they couldn’t part with from the 4,200-square-foot home they gave up on a half-acre in Belleview, Wash., when Rob Howe took a job at eBay.

The tour’s big reveal was one of the penthouses on the 21st floor. Engineers Paul Teixeira, 35, and Jose Mendez, 28, own this 1,700-square-foot home with two bedrooms, two-and-a-half baths, 11 1/2-foot ceilings and floor-to-ceiling windows. “It’s like a glass box in the air,” Teixeira says.

Teixeira was happy to give up his four-bedroom, two-story house in South San Jose that kept him doing yard work on weekends for the penthouse with the views from the eastern foothills all the way to San Francisco. Both men take the light rail to work most days. About the only things Teixeira kept from the old house were his childhood piano with the varnish flaking off (“It’s rustic and kind of weird,” Teixeria says) and the massive sectional that fit perfectly between two support columns.

“It’s that modern rustic, a cross between Pottery Barn and Restoration Hardware,” he says of the comfortable, low-profile couch. “Neither of us are ultramodern. We were trying to shoot for that clean modern look, but a little bit warmer.”

The bar with the LED-illuminated shelving is new — lighting up his liquor bottles in an array of colors — along with the outsized artwork on the walls.

Before moving in, the couple modified the kitchen, adding a huge granite-topped island that has become party central. To add color to the mostly black-and-white palette, they added a trio of blue pendant lights over the island.

They also made a centerpiece on their seldom-used dining table with a giant ceramic abalone shell and blue and green blown glass that practically glows when the natural light streams through it.

As much as the couple enjoys the inside of their penthouse, it’s what’s outside that made them fall in love with it. On a clear day, they can see the Golden Gate Bridge.

Here’s the complete slideshow: