Electoral officer Warwick Lampp told the Bay of Plenty Times the byelection for the Pyes Pa/Ōtumoetai ward seat will cost ratepayers $100,000. The cost of holding the mayoral byelection at a separate time would have cost $210,000. However, the cost for both byelections is expected to cost between $230,000 and $240,000.
If a sitting councillor is elected mayor in the byelection, the cost to run a subsequent byelection to fill their councillor role would cost $100,000, Lampp said.
A Tauranga City Council spokeswoman said sitting councillors were able to stand for the mayoralty and did not need to resign from their present role to do so.
However, if a sitting councillor was elected mayor, a byelection would be needed to help fill the vacancy left by that councillor.
The current elected members' team consists of three people who ran for both the mayoralty and councillor roles in last year's election. They are councillors Andrew Hollis, John Robson and Kelvin Clout, who also has previously served as deputy mayor.
Hollis has already ruled out running for the mayoralty role, telling the Bay of Plenty Times he'd prefer to win the role in a general election rather than through a byelection.
Hollis said he would prefer to support a contender with more experience in governance, such as former mayor Greg Brownless or Clout.
Clout confirmed he still had aspirations for the mayoralty but was not certain now was the appropriate time to stand.
"I believe I have a lot to offer, particularly in my leadership style which is quite collaborative in getting around the table with my colleagues.
"But in terms of if and when, it's probably more a matter of when than if. I'm not rushing to make a decision on that. Obviously, what came on Friday came as a shock to all of us so I'm taking time to consider all options."
Clout said the fundamental issue was what would come from Local Government Minister Nanaia Mahuta, who is yet to decide whether to bring in a Crown manager and observer to help the council (as what was voted for on Friday) - or bring in commissioners to take over the council (as called for by Powell in his resignation speech).
Robson said he remained undecided for now and declined to comment further, citing the uncertainty looming over the council at present.
Brownless said he would wait for the minister's decision before making any of his own.
Lampp said a double byelection for two council seats at the same time was "very rare".
"It doesn't happen very often but it has happened before," he said.
"I've had a one where a byelection started for a councillor position, then someone else resigned, then we combined it and held it together. That was about 15 to 20 years ago."
Tauranga elected members met privately yesterday for an informal debrief following Friday's developments and before an Urban Form and Transport Committee meeting today.
Minister Mahuta's decision is expected to be made sometime during the next few days.