The by-laws of the corporation will have a paragraph, Removal of Officers and Directors, or similar heading. If not, removal is by statute. Generally, it will take more than 50% of members or a higher % of directors, could be unanimous consent.
It also takes time, as you need to give notice of a special meeting for the removal of the officer, stating the time and place of the metting and purpose.
There can be some tactics involved, say you need to remove two or more, trying to can all of them at one meeting might be tough. Your will most likely need to vote on one member at a time and if it's the board voting, the others may have the right to vote. Officers considered for removal may not vote on the issue. So, when you begin, you might pick the worst one first and stay quiet about the other, the take them on later, so it could take time to pick them off one at a time. This can be done without an attorney, but considering the size and scope of the problem, probably best to hire one.
The other way as mentioned above will be to sue, having more than 50%.
Another tactic would be to notify the bank making the loan and inform them that this project is under protest and that action against the corporation is being taken....they won't make any loan until the matter is settled.
Was the bid for the siding accomplished according to the by-laws, were bids taken? Do you know of any relationship between any of the officers and the company doing the work? DId they take the lowest bid?
Work out comps on your building and value the units with the new expense, you might show MV being lower. You might ask an appraiser for a letter of opinion as to the impact to market value with the improvement.