Is zakat obligatory on the remaining amount from the sale of a building that has been for sale for a year, after paying off debts?

If one prepares a building for trade, then its price is subject to zakat. One pays zakat on it if a year passes from the intention of trade. However, if one did not prepare it for trade, but rather their need for it ceased and its sale was delayed, then there is no zakat due on its price. Zakat is only due on the portion of the price received, once a year has passed on it.