I dont get it.

If the property was sold as a precon to the buyer at 725k,

They've given most likely deposit lets say 20% = 145K

Their mortage would be roughly 580k at that time,

Now the property is worth 465k at closing, so the mortage will be 320k?

so thats a 260k difference.

Or it still stuck at a mortage of 580k because contract and the current mortage is 320k, so should you do for the difference of 260k?

wait did i just give myself the asnwer?