As a reminder, a mortgage certificate is an official document issued by a notary that serves as security for a mortgage loan. You cannot borrow money from a bank without this “security paper.” Issuing it costs around 2% of the mortgage amount (including registration fees, land registry fees, notary fees, and various expenses).
In the context of a transaction, the transfer of the mortgage certificate is part of the negotiations. Generally, unless the seller chooses to transfer it to another property in their name, the certificate is transferred to the buyer for half of the creation costs mentioned above, i.e., about 1% of the mortgage amount. For transactions involving a large volume, it is sometimes customary for the certificate to be transferred free of charge.
Excerpt from our guide: Selling Your Home in 42 Questions