Manson said the site was bought from Victoria Quarter No 1 by Manson's and CMP Construction.
Mansons TCLM was the majority owner and was taking the lead role in the construction, with design input and expertise from CMP Construction.
"We have named the development The Boutique," he said. "At this stage it is too early to confirm rents, but we will be looking for long-term leases for each unit."
The carpark has 200 spaces. Mansons will add an extra 30, but will disguise the building with an aluminium wrap.
"The car park, which is an eyesore, will be removed from view and beautified with screening and planting of trees," Manson said.
Steel beams would be lifted on to the top of the existing building to create an extra three levels at one point and five levels at another point.
"Because the site is a gateway corner location, we are getting extra levels," he said.
Mansons built the Lumley Centre on Shortland St and Telecom's four-building campus further up Victoria St West.
It is now developing a 20,000sq m office block on the corner of Graham St and Victoria St West, to be finished by late next year.