Open Question: What can we do if one condo association trustee defies the group and does unauthorized work on the building?

We are part of a three owner condominium association. We are in a difficult financial situation where one owner who has been in charge of the books for the last 4 1/2 years says he's all paid up on condo fees, but we need to look at the bank statements. The other two of us have been delinquent in fees, but I am about to be all caught up. We had a condo meeting where we agreed to not do any work over $100 until we had a meeting. We woke up to work being done on the outside of our building. We asked him what he was doing. We told him that we had agreed to not do any work until we had a meeting. He defied us and went ahead and began doing work on the building purchasing used shingles. What can we do in this situation?