Über wealthy clients of Citigroup are financing construction on a long-delayed 4.5-acre project set on West Hollywood's Sunset Strip.

Citi's private bank clients are helping fund developer CIM Group's high-profile $300 million-plus Sunset La Cienega project, which includes a hotel tower and a multifamily condo, according to Dan O'Donnell, the global head of private equity and real estate for Citi's private bank.

The West Hollywood project sits on two city blocks and is located on the corner of 8490 West Sunset Blvd., according to co-investment partner and developer, CIM Group, which first acquired the property in 2011. The 296-room hotel and 190-unit, eight-story condo will be surrounded on the strip by retail shops and restaurants, according to the developer's website. It is one of several such projects that Citi's clients are known to be funding.

Funding for as many as four commercial real estate projects on the West Coast has been raised to date, according to two officials involved with project planning.

A similar club is backing construction on 432 Park Ave. in New York. It will be the city's tallest new apartment building. Several hundred of Citi's wealthy clients are participating in that project, and it achieved "material oversubscription" by several multiples. A third investment fund is backing a 60-story residential tower and separate hotel under development by Carpenter & Co. in Boston.

The firm's clients have even capitalized a project in Brooklyn, O'Donnell said in an interview.

"I'm looking for fully capitalized, shovel-ready, zoning-ready projects with equity and debt funding locked up," he said. "We are ringfencing 25 to 50 billionaire families together for these funds."

A minimum buy-in is no less than $500,000 to $1 million, according to O'Donnell. The returns are very rich, and usually monetize by their fifth year, he said.

Citi's private bank has each year for five years deployed around 15 new funds to invest in global real estate and distressed assets, raising around $2 billion from its wealthiest clients who have net worths in excess of $25 million, according to executives under newly named private bank head Peter Charrington. Its so-called investment "clubs" are designed to allure its even more affluent clients with return estimates ranging from 15%-20%.

The unit has partnered with a number of private-equity partners on projects, including Blackstone Group, Carlyle Group, the U.S. middle market fund Silverfern Group, as well as U.K. real estate investor Threadneedle Investments.

Wealthy investors have insisted since the downturn on access to U.S. urban commercial real estate, but that is not all. Also in high demand is more access to fund U.S. energy projects in the Southwest. In Europe, distressed opportunities are still proving fruitful, buyout advisers say.

Citi's wealth unit has client-funded projects ongoing in each of those regions.

The bank's exclusive clients have also committed some $500 million with private-equity giant Cerberus Capital Management, which has honed in on European banks' derisking. That fund is now closed, with money still being deployed for new originations. Citi could partner again with Cerberus in 2015, O'Donnell said.

Matt Scully is a reporter for American Banker. 

Read more: