Just to clarify, if there is a mortgage on a property, then the lender will hold the Deeds and will only release the deeds to a solicitor on A.T. R. ( Accountable Trust Receipt- won't part with deeds unless can discharge entire mortgage or a figure agreed with the lender).
It is quite usual now for a vendor's solicitor to ask their own client for a recent mortgage statement or ask the Bank/lender for redemption figures before drafting Contracts for sale.
If the property is not in negative equity then the sale price will cover the redemption amount to clear the mortgage.
If in negative equity, then the vendor must approach the lender to see what, if any, arrangement can be arrived at in order to sell the house. A purchaser must be certain that the vendor's mortgage will be cleared off the title or else they cannot proceed.
I have had clients purchase properties where the vendor's lender has confirmed, in writing, that they will clear the mortgage off the title on foot of a contract price specified. What arrangement they come to with their client I do not know.
mf