Bonnie McIlvaine has lived in three homes in San Diego County, all on the very same spot.
The first was an unheated concrete-block house she bought in 1973 for $32,000. A newly divorced schoolteacher, Ms. McIlvaine wanted a break from urban living. She found herself in a small, hilly town with stretches of undeveloped brushland and woodland, not far from the coastal city of Carlsbad, Calif., where she worked.
As she cast her eyes lovingly on the frumpy little building — or, more accurately, on the half acre it sat on — her real estate agent told her, “We can do much better; we’re going to look at tract houses.”
But all Ms. McIlvaine could think of was that she had always wanted a horse, and maybe that could happen here.
In 2001, the year she retired from teaching, she invited her mother to come live with her. The women pooled their money and replaced the concrete house with a two-bedroom bungalow that had a gabled roof and central heating.
Today, that building is quite another thing: a place where Marie Antoinette might have happily kicked off her slippers and flopped on a chaise longue.
In 2007, Ms. McIlvaine, who is now 80, inherited a fortune from Hubert de Monmonier, a neighbor she had met on horseback decades before and with whom she had formed a deep, platonic friendship.
“My dad was killed in World War II,” she said. “I didn’t have that close, comfortable, male counterpart.”
Mr. de Monmonier, who was 23 years older, shared her love of literature, gardening and animals. “We just hit it off,” she said. And one day, he told her that in the absence of any close living family members, he intended to establish a trust for her.
Mr. de Monmonier had been a groundskeeper and metalworker for the Los Angeles Unified School District, but made his money through a shrewd real estate investment followed by successful stock trading. (A rockhound, he had also amassed almost 900 geological specimens, which he bequeathed to the University of Arizona Gem and Mineral Museum.)
With her inheritance, Ms. McIlvaine paid for the college education of two of his Mexican gardening assistants. But she also chased a dream that had ripened during summer travels to the Cotswolds in England and the Palace of Versailles in France: She reinvented her 1,600-square-foot bungalow as a place surfaced in weathered stone and vintage wood, hung crystal chandeliers from the elevated ceilings and filled it with antique furniture.
Tiffani Baumgart, the interior designer who was Ms. McIlvaine’s partner in the transformation, described the intensively embellished little house as a “micro Versailles.”
Having appeared on the scene after the bungalow was gutted and its interior in the process of being reconfigured — following the death of Ms. McIlvane’s mother in 2009, the second bedroom was turned into a garden room — Ms. Baumgart spent more than three years applying the theme of baroque luxury to every square inch.
She hired woodcarvers to execute her rococo cabinetry sketches. She organized the production of custom marble floor tile. She worked with Ken Wildes, a plaster artist based in Newport, R.I., on the installation of 250 handmade roses on the living room and bedroom ceilings. She oversaw the murals painted by Jennifer Chapman, a local artist.
“Jennifer was in the house for years,” Ms. Baumgart, 61, recalled. As the artist made her way from room to room, painting birds and butterflies, billows of blossoms and pink-tinged cumulus clouds in cerulean skies, she settled into a Fragonard-like groove. When Ms. McIlvaine and Ms. Baumgart failed to find an antique baby grand piano that would blend into the living room, Ms. Chapman painted a newly acquired Steinway with gold flounces and scenes of pastoral ruins.
Even rare acquisitions got a personal stamp. Many of the 18th-century furnishings found through dealers or online searches were recovered in velvets, silks or Fortuny prints. Ms. Baumgart cut down and reconfigured a pair of cumbersome candelabra into the matching pendants that now hang over the kitchen island and commissioned metal workers to twist iron into stands to support antique stone basins in the powder room and laundry room. A carved panel she found in an antiques shop became the centerpiece of a bedroom closet.
At other times, the environment was altered to accommodate beloved purchases, as when an arched niche was designed into the living room’s crown molding to make way for the knobby top of an Italian gilt mirror. The arch inspired the curved doorway on the other side of the room.
The house was effectively completed in 2012, but Ms. Baumgart continues to noodle with it; she recently added custom outdoor draperies to a secret garden area.
Was there ever a point, she was asked, when her client shut down an idea or purchase because it cost too much?
Never, the designer said.
Which raised the delicate question of budget.
“I got all of my bills, and I stuck them in a folder,” Ms. McIlvaine said. “And I thought, ‘Someday I’m going to just add everything up.’ And then I threw everything away.”
She added, “My guess would be a couple of million.”
It is likely that anyone familiar with the price of custom plastering and original Louis-something furniture would suspect that this estimate was low. But the more burning question was why, with her windfall, Ms. McIlvaine chose to invest so heavily in a modest bungalow.
“People have said, ‘The neighborhood isn’t very upscale. If you’re spending all that money, you should move to Rancho Santa Fe,’” Ms. McIlvaine said, referring to an affluent residential community near Carlsbad.
But she never wanted to renounce the property that stole her heart more than 50 years ago, she said. Although the horse she owned is now a cherished memory, she has a pair of dogs, a pair of koi ponds and a waterfall fed by a recirculating irrigation system.
“Have you ever heard of people that win the lottery and then suddenly they’re out of money, and they don’t know where it went?” she asked. “It’s kind of like that. So I’m cooling my jets. I’m not spending any more money. I’ve already got my little paradise.”
Living Small is a biweekly column exploring what it takes to lead a simpler, more sustainable or more compact life.
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