"It has cost money for our ratepayers, and we had to ask them, but we heard thousands and thousands of submissions from our community who told us, please restore and protect these buildings," she said.
The pōwhiri attracted hundreds of people and was also an opportunity to relive some of the grand building's many memories.
Tukituki MP Anna Lorck remembers many school balls and events in the Municipal Building.
"As I walked up the stairs back up to the assembly hall, all those memories came flooding back.
"It's hard to believe that Hastings has been without this for eight years."
Lorck said it was a magic moment for Hastings and brought the whole city and district alive.
The Municipal Building, as part of Toitoi, is expected to generate business.
Toitoi corporate services manager Coltan Wright says he can't wait to start bookings.
"Toitoi is a fully equipped convention centre.
"The Assembly Ballroom hosts everything from weddings to gala events to dinners to quiz nights. The Shakespeare room is a fantastic space for workshops, daily meetings, and cocktail functions."
The eight-year restoration project cost about $23 million and now it was time to recoup that investment, he said.
The Municipal Building offers a ballroom and different-sized meeting rooms for venue hire.
The Assembly Ballroom is Hawke's Bay's largest sprung dance floor, with a 400sqm floor space, a 5m ceiling, and holds up to 400 people.
New eateries and bars are also open on the ground floor on Heretaunga St East.
A revamped Hastings Information Centre has relocated to the Municipal Building.
The Quest Hotel, which will have 34 fully serviced rooms, is under construction, adjoining the Municipal Building.
It is due to be completed in December to make Toitoi a one-stop business centre.