Pre-2011 balcony enclosure

Do you have approvals from the coop board for the alteration when the enclosure was put in place? Or DOB filings for the enclosure which someone from the coop board or managing agent would have had to sign? If not, you will need a lawyer to look at the situation in more details. Coop can usually do what they want outside the walls of your apartment - the removal of enclosure basically becomes facade work.

Why is the board coming after you now? Is it a case that other similar units don't have enclosures? Do you have something that you can trade with the board?

You want to try to handle this before it escalates to lawyers, if possible, and thinking about the board's motivation is part of that.

ali r.
{upstairs realty}

Just be aware that the Coop's attorney is probably telling the Board that they can do WTF they want because they profit from litigation.