The development of the Áras Phádraig site on Lewis Road in Killarney could cost up to €50 million.
The cost emerged at a recent meeting of Killarney Municipal District.
Director of Services for Kerry County Council, Michael Scannell told the meeting that the council had engaged an architect firm to develop a plan for the town centre site.
Mr Scannell said the development will require public and private funding.
Proposals for the plot, which is part of an overall seven-year development plan for the town, includes a theatre, community space, office space and car parking.
The Áras Phádraig building has been lying idle since it was donated to the town council by the Franciscan Order in 2009 because of legal difficulties.