Mr Birrell said Vos Constructions would build the dealership complex on the existing Motors used car site at 170-178 Elizabeth St.
Motors is moving after selling in October its main 7390sqm site at the corner of Bathurst and Frederick streets to Launceston entrepreneur Joe Chromy.
The Car Mart business has been moved from the Elizabeth St site to Hobart Rd, Youngtown, to make room for the development.
It is planned to build several podiums, new car showrooms, car servicing workshops, hospitality, administration and training areas on the Elizabeth St site.
Mr Birrell said the dealership would be Australia's first fully realised vision of the new Holden corporate image.
Mr Ted Ashton, of ERA 2000 architects, said the building would use an extensive amount of glass in a bid to reflect a sense of transparency and trust necessary between customers and the business.
Mr Birrell said that since he bought the business in March 2001, the Hobart and Burnie showrooms had been renovated, a truck service and bodyshop had been bought in Hobart and a truck service workshop created at Connector Park in Launceston.