High-flier Derek Quinlan whose investments have been hammered by the global crisis

 One of Ireland's most high-profile property tycoons is stepping down from his own investment company.

Derek Quinlan, 61, is retiring as chairman and partner of Quinlan Private after 20 years at the helm.

A former tax inspector, Quinlan founded the firm in 1989, just ahead of the property boom, to offer tax advice to Ireland's elite.

The company expanded aggressively and is now a multibillion euro property firm with clients and investments in more than 15 countries.

Quinlan shot to international prominence in 2004 when it emerged that he was the lead investor in the €1.1 billion purchase of London's luxury Savoy hotel.

He also made headlines in New York in January 2006 when he dropped $40m on two townhouses on 64th Street.

However, he put both of them up for sale in June leading to fears about his cash flow.

Quinlan, who is one of the biggest supporters of the US-Ireland Alliance, cut $14m off the new asking prices last month.

He cut the asking price of his 64th street mansion from $37m to $32m and his 64th street office from $36m to $27m.

The so-called "deal junkie" has also pulled out of his management role at the firm to focus on his personal portfolio.

Quinlan Private made billions during the property boom by facilitating quick deals for wealthy investors backed by massive bank loans.

The strategy was simple; Put up the cash, borrow the 90 percent and sell at a much higher price within a couple of months.

It was a high-stakes game for the wealthy who could afford to stump up $1 milion deposits and subsequent mortgages until the property or development was sold.

However, the speed of the global collapse has left many wealthy investors exposed to massive debts.

The banks have been forced to renegotiate with investors such as Quinlan Private - and Quinlan himself - to try and get their money back.

The massive declines in the property markets makes that prospect unlikely which might explain the discounted Quinlan mansions on sale on East 64th Street in New York.