Preparation for the final stage will involve the remaining construction works such as roading changes, landscaping and seating.
Owner at Payless Supplements on Tutanekai St said the amount they'd closed off was "stupid", especially when it's for three months.
"We weren't expecting it to be that much," he said.
"It's blocking about 50 per cent of my foot traffic."
One Rotorua local said it was a huge nuisance.
"There's no signage on it, so you don't know why it's closed or how long for," she said.
"I think it's unfair for the businesses."
She said there was very little notice given, as she didn't even know it was going to be closed.
Fletcher Construction has agreed to a fixed price of $1.135 million for the third stage. Work to date has cost a total of $231,000 and the project will be completed within the budget agreed in the long-term plan, the council said.
Rotorua Lakes Council said noise and disruption would be kept to a minimum.