The wealthy residents of an exclusive San Francisco street have threatened legal action after learning that the communal areas outside their homes have been sold to a private investor for a combined total of just £70,000.

Despite the street’s mansions selling for millions of dollars, an unpaid tax bill saw the carefully manicured lawns and pristine pavements of Presidio Terrace auctioned for a mere $90,000.

Michael Cheng and his wife Tina Lam bought the gated street and now own the road, footpaths and other areas of "common ground" in the private development.

The auction stemmed from an unpaid bill after the homeowners association for Presidio Terrace failed to pay a $14-a-year property tax, something that owners of all 181 private streets in San Francisco must do, the San Francisco Chronicle reported.

The Californian city’s tax office put the property up for sale for $994 in an online auction to claw back unpaid back taxes, penalties and interest. The couple eventually won the street with a $90,100 bid in an April 2015 auction.

But Scott Emblidge, the lawyer for the Presidio Homeowners Association, has blamed an administrative mix-up for the missed payments.

According to a letter seen by the Chronicle, he said the owners failed to pay because the tax bill was being sent to the address of an accountant who hadn't worked for the homeowners association since the 1980s.

Mr Emblidge said the residents didn't know their street was put on the auction block, let alone sold, until May when a company hired by the street’s new owners contacted residents to ask if any were interested in buying back the rights to land immediately outside their homes.

Loading....

Mr Cheng and Ms Lam are said to be looking for other ways to make money from their investment, including charging residents to park on their street or renting out the 120 parking spaces that line the road.

"I thought they would reach out to us and invite us in as new neighbours," Mr Cheng told the Associated Press.

"This has certainly blown up a lot more than we expected."

A seven-bedroom property on the street recently sold for more than $17m and the real estate investor, who was born in Taiwan, said he "got lucky” with the auction two years ago.

A construction worker stands in front of a gate leading into the Presidio Terrace (AP)

"As legal owners of this property, we have a lot of options," he told the Chronicle.

“I’m a first-generation immigrant, and the first time I came to San Francisco I fell in love with the city.

“I really just wanted to own something in San Francisco because of my affinity for the city."

However, the street’s residents have attempted to block the new landowners by petitioning the city’s Board of Supervisors for a hearing to rescind the tax sale. The board has scheduled a hearing for October.

The homeowners association has also sued the couple and the city, seeking to block them from selling the street to anyone while the appeal is pending.