The State Ports Authority has hired a Columbia real estate firm to help it sell nearly 500 acres on Daniel Island that the agency once planned to develop into a major shipping terminal.

The vote at Tuesday's board meeting will enable the SPA to finalize a listing agreement with NAI Avant and its affiliate, NAI Global.

As part of the arrangement, the maritime agency and the Midlands-based brokerage will establish a new asking price for the 495-acre tract. The most recent appraisal, which has never been disclosed publicly, is about two years old.

The effort to sell the property comes amid one of the harshest real estate markets in decades, with most banks unwilling to underwrite loans for speculative large-scale land purchases. In all likelihood, any serious buyers will have to come to the table with cash.

"Probably the biggest challenge in the current development climate we're in is the financing element," said Gene Green, chief operating officer and broker in charge of NAI Avant.

The SPA has about three years to find a qualified buyer for the land, which is on the Cooper River side of Daniel Island and boasts extensive waterfront acreage. Under state law, the maritime agency must have a contract in hand by the end of 2012 and finalize the sale by the close of 2013.

Green said the site will be marketed nationally and internationally through the Internet and NAI's global network of real estate partners.

"We think this is a unique and special opportunity for someone, and we feel like we're going to be able to generate some good quality interest in the property," he said.

The SPA acquired the site in the early 1990s with plans to turn it into a huge container terminal called Global Gateway. Opponents rallied

lawmakers, who then steered the new port terminal across the Cooper River to the former Navy base in North Charleston.

In 2006, the SPA put the Daniel Island land up for sale and attracted interest from 18 developers but then took it off the market to re-evaluate the site and its options.

Last month, the SPA solicited listing agreements from South Carolina-based brokerages that are affiliated with national or international real estate companies. Firms were asked about their experience selling similar properties, their marketing strategy and projected fees and expenses.

The SPA said the specific terms of the agreement with NAI Avant had not been finalized as of Wednesday.

Three firms with Charleston-ar ea real estate offices also submitted proposals: CB Richard Ellis/Carmody; Coldwell Banker Commercial Atlantic International; and Colliers Keenan Charleston. Grubb & Ellis|The Furman Co. of Greenville also sought the listing.

Reach John McDermott at 937-5572 or jmcdermott@postandcourier.com