Veteran antique dealers advise newcomers to their business to avoid a common two-edged mistake: Paying too much for some item they simply must have for display in the shop window; then, setting too high a sale price on it, hoping to recover their investment. The precious trinket sits unsold, gathering dust for months, even years.

It sounds a little like the love affair the Redevelopment Authority of the City of Butler seems to have with its own high-priced entry into the antiques market — the Penn Theatre.

The authority borrowed money in 2007 to buy the 17,500-square-foot, 75-year-old structure on North Main Street, even though the Penn has sat vacant and has been deteriorating for years.

The lender of that money, the Pittsburgh History and Landmarks Foundation, holds the $250,000 mortgage to the Penn. The authority had been paying the foundation $2,200 a month until last May after the state stopped allocating funding intended for a rehabilitation of the Penn. In the nine months since then, the authority has paid nothing — essentially putting the property in default.

The root issue is that the old theatre in its current state is worth far less than the authority paid for it; the cost of restoration is even further out of reach, particularly with the cutoff of state funding; and the Pittsburgh History and Landmarks Foundation won’t foreclose on a property worth nowhere near the amount of money the foundation is owed for it.

Last week, the authority board voted to attempt selling the property for less than what it owes on the mortgage. Real estate folks call this kind of transaction a short sale.

Executive Director Art Cordwell says the authority remains on the hook for the mortgage and could not find a buyer willing to pay the full amount for it — but he said there’s someone willing to pay less.

That would be a splendid development, but only if it happens quickly. While some antiques increase in value as they age, the Penn Theatre is not one of them. It has become an eyesore in the middle of our county seat. And options for restoration are not increasing over time, either.

City officials should set a deadline for improvements, and then enforce the deadline.

From a sentimental standpoint, the memory of a downtown theater has some value, but to be practical about it, any plan to restore the Penn will need to include ways for it to attract visitors, income or both. Otherwise it’s just a high-priced curio in the front window, gathering dust.