Is zakat obligatory on the entire remaining amount in the bank, or only on the portion remaining from the amount designated for purchasing the land, after paying a down payment?

If the sale is concluded, the amount paid as the price of the land is exempt from zakat. As for the remaining debt, it is deducted from the wealth subject to zakat according to the majority of scholars. However, it is not deducted according to the Shafi'is. According to the Malikis, it is deducted if the debtor does not own an asset that can be used to cover the debt. But if the sale is not concluded, and what was paid is a earnest money deposit (non-refundable deposit), then all the saved money, including the deposit, is subject to zakat.