With the time dwindling until an official go-ahead to demolish the La Ronda mansion in Bryn Mawr, a preservationist group posed for a photo this week - only yards from workers hauling what looked like fixtures, including sinks, out of the house and into an unmarked van.

Whether the immense villa was staying or going depended upon which side of its iron gates one stood at. Lower Merion officials ordered a halt to the dismantling until more paperwork could be filed, but the 80-year-old mansion's demolition has not been as easy to stave off.

The township is lobbying to preserve the place despite having given to its owner in June a demolition permit that can be used as of Sept. 1.

Tomorrow, the Lower Merion Conservancy plans to declare La Ronda, designed in 1929 by the famed Florida architect Addison Mizner, the most endangered property on its watch list. A Web site (savelarondanow.com) and Facebook group have been set up, and pledges to support buying the house are being collected by the township historical foundation.

Yet despite the attempts to drum up a debate, the fate of the castlelike Spanish revival mansion is fast becoming a matter as shielded from public view as the real identity of its owner.

Although officials said they are still soliciting donations, their priority has shifted to finding a deep-pocketed buyer, perhaps ahead of deciding on an ensuing use for the house should it be preserved.

"The object at this point is to prevent the demolition of La Ronda in early September," Township Commissioners Chairman Bruce D. Reed said.

The owner plans to raze the estate to build a 10,000-square-foot house for his family, but has said through his attorney that he would entertain offers.

Reed and others said a prospective buyer has been found who this month approached Joseph C. Kuhls, the owner's attorney. The potential buyer said Kuhls had not responded, Reed said.

Kuhls wrote yesterday in an e-mail that he "personally and promptly responded to all inquiries from potential buyers." There have been three individuals, he wrote, but none has tendered a written offer.

Neither Reed nor Kuhls would identify the prospective La Ronda buyers they have encountered. Reed cited the sensitivity of negotiations and the potential buyer's desire for privacy during early talks.

The mansion's owner, whose name has been concealed by a corporate front since the $6 million purchase in March, allowed a group of eight township officials and preservationists a glimpse last week at what could be lost.

Pictures posted at savelarondanow.com indicate that much of the ornate wood, iron and glass creations that the leather-tanning magnate Percival Foerderer commissioned remain in solid shape.

"It's got a very medieval flavor to it," said Kathleen Abplanalp, an architectural historian who joined the tour.

She found the house "spectacular."

"It was as if actually I stepped into a chapter of my own dissertation," Abplanalp said.

Contact staff writer Derrick Nunnally at 610-313-8212 or dnunnally@phillynews.com.