A council is continuing to pay business rates on a building it has not been able to use for almost three years.
A bill of £234,800 has been paid by Conwy council on top of £391,500 it paid in rent for the depot at Mochdre Commerce Park, near Colwyn Bay.
It began paying rates when it signed a lease in May 2016, but it has been unable to use the building as a depot for HGVs because the floor is too weak.
The council said it was confident it would reclaim business rates.
It emerged in July the council had paid almost £400,000 in rent. The authority said on Thursday it had agreed a freeze on rent with the landlord in June, so the figure had not increased since.
'Very sobering read'
A meeting was convened behind closed doors on Thursday in order to look at ways to resolve the situation.
In a statement, Conwy council admitted it "fell short of our own high standards" and that an independent review had found "process failings".
"The report into how the situation at Mochdre came about is a very sobering read, with many parts highlighting weaknesses in our processes which we don't normally see," said councillor Sam Rowlands, the member with responsibility for finance.
"We must take on board the recommendations to ensure the errors highlighted do not happen again and to allow us to move forward with what has been a very difficult piece of work."