Rising buyer stock portfolios, bigger discounts and cash purchases are driving sales across U.S. vacation property spots up to the highest levels ever since the last economic boom. Waterfront sales on Mercer Island, Washington have tripled last year compared to 2009 figures, equaling sales records from the year 2006.

Vacation property sales in Hilton Head Island, S.C. also rose by as much as 14 percent. Sales in Palm Beach, Fla. meanwhile soared to a 40 percent increase over the year, with a 54-percent rise for homes under contract signaling a very strong final quarter for 2010. With the latest increases, Palm Beach sales have equaled figures recorded back in 2007, the highest yet.

Sotheby, Palm Beach agent Ned Monell of International Realty comments of the recent boom in the industry that the "proverbial train has left the station." Monell explains that their business has not felt so energetic until now, with buyers now leaving the sidelines and coming up front.