Once the new mortgage agreement is signed, then you can obtain the value of the original note. Once the new mortgage is paid off, then you can claim back the value of the new note. Each agreement you sign is another note, the value being whatever is the stated face value on the agreement, which can be demanded back once the business is complete. I have retrieved the mortgage details from the solicitors who did the conveyancing (some agreements were completed more than 10 years ago). They will give you the mortgage company, purchase date, amount 'borrowed' and the account number.