Debate over the cost and scope of the work, along with turnover on the volunteer board, dragged out preparations for the repairs for three years, according to previously unpublished correspondence, condo board minutes and other records kept by the homeowners association. Concrete restoration work had not yet begun when the building partially collapsed June 24. Identifying the cause of the catastrophe is expected to take many months, and it is not clear whether the problems identified in 2018 played a role. At least 18 people were killed in the catastrophe, and 145 remain missing. Despite increasingly dire warnings from the board, many condo owners balked at paying for the extensive improvements, which ballooned in price from about $9 million to more than $15 million over the past three years as the building continued to deteriorate, records show.