And a supermarket for the suburb is a step closer as expressions of interest for the site are being sought.

The first stage of the development at 30-32 Blackall Street is under construction and completion of the 136-apartment complex is expected early next year.

The transformation of the car park site, bordered by Blackall, Macquarie and Broughton streets, has been brought forward partly due to the impending introduction of paid parking in the Parliamentary Triangle in July.

Morris Property Group and the Doma Group have lodged a development application with the National Capital Authority for a structured car park and retail facilities.

The developers' documentation for expressions of interest in a supermarket says that while the space allocated for it is planned to be between 600 and 800 square metres, they developers would consider larger or smaller formats.

The expressions of interest have to be lodged with the Doma Group by May 2.

Doma Group director Jure Domazet said it was expected a start on the supermarket would be made later this year and it would be completed by mid next year.

"There is strong interest in all of the retail available in the building,'' Mr Domazet said.

''However, it is best for us to look at the supermarket premises first as the smaller tenancies can fit around it.''

Mr Domazet said large operators like Coles and Woolworths would be given the opportunity to lodge a submission as well as local operators, but "the building does not lend itself to a full-line supermarket".

He said the two companies had only just decided to proceed with the third stage as further residential development following the success of the first apartment complex on the site.

Design work has begun and construction is expected to start in the first half of next year on what will be the final stage in the development of the car park site.

Doma Group and Morris Property Group bought the site for $16.5 million in a joint venture in 2010.

Later that year it was turned it into a paid parking area.

While plans had originally been for office buildings to fit in with the office precinct, a tender could not be arranged and the companies changed direction.