The Massachusetts Convention Center Authority has reportedly drawn up plans to spend $33 million to purchase a 5.5-acre vacant lot in South Boston as the first step in a $2 billion expansion of the Boston Convention and Exhibition Center.

Both the Boston Globe and the Boston Business Journal report that the land is to be used for hotels and parking.

Michael Widmer of the Massachusetts Taxpayers Foundation says Boston needs expanded convention capacity, but questions who will pay for it.

“The overarching question is how are the taxpayers of Massachusetts going to pay for it? It’s a question of cost and benefit,” says Widmer. “The expansion of the Convention Center is undoubtedly a good thing and would allow conventions to come here that otherwise wouldn’t. But then, at what cost?”

Widmer points out that money is also needed elsewhere.

“It’s not as if we are flush … that we, the state budget is flush … with cash and there are no other competing interests,” says Widmer. “For example is it better to invest in a convention center authority or to invest in the MBTA and public transportation, or improving our roads and bridges across the state?”

The Convention Center Authority refused to talk with WGBH about its South Boston expansion plans. The authority, however, would likely need state lawmakers to agree to tax increases or other public funds to finance the project. Funding talks with state officials are still in the early stages.