A luxury Lake Como-inspired estate in the San Francisco Bay Area has sold to a buyer “in the AI world” for a record $70m, in the latest sign of a new tech wealth boom that’s pushing home prices to extraordinary heights in the region

The property south of San Francisco not only becomes the most expensive sale in its affluent town of Hillsborough, doubling a previous record, but is also the most expensive sale in northern California this year, according to listing agent Jennifer Gilson of Golden Gate Sotheby’s International Realty.

Gilson declined to share any details about the buyer, other than that the new owner of 3000 Ralston Avenue is a man in the AI industry. It is the latest sign of a housing boom across Silicon Valley being driven by AI wealth. Last month, an analysis found that more than 140 San Francisco homes have sold at least $1m above their asking price in the first six months of this year.

The property, known as “Villa de Verano”, was initially listed at $88m, and sat on the market for only four months and 22 days. Besides a six-bed, 12,400 sq ft home that is complete with its own gym, theater, spa and aquarium, the 12-acre property also features a pool, a rose garden, an amphitheater, a guest property and a sporting area fitted with seven courts and a putting green. Its opulence stands out even among other palatial Hillsborough homes, which include Bing Crosby’s $25m home, Elon Musk’s $32m former home and the Levi Strauss-connected $17.8m Koshland Estate.

Yet Gilson says this sale is only a “stepping stone” into a market of homes catering to the incredibly wealthy.

“Even in the last year, there’s been a major increase of buyers from the AI world,” she said. “This could be just the beginning of the ultra luxury.”

Since the San Francisco-based companies OpenAI and Anthropic filed for initial public offerings earlier this summer, a new class of multimillionaires has entered the real estate race. An analysis by brokerage Compass described a “housing market increasingly segmented by income tier and proximity to AI-driven employment centers”.

Gilson said she has seen an influx of wealth among buyers coming not just from AI companies, but increasingly from other, traditional industries. She described a “definite increase” in those ultra-rich buyers taking off-market, “hidden” opportunities, meaning Gilson connects buyers to sellers without homes ever being listed.

In San Mateo county, where the sale took place, the median price of a single-family home increased by 8.5% between May 2025 and May 2026. San Francisco county saw a more than one-fifth increase, with median prices jumping from $1.8m to $2.2m.