Regarding the Leaseholder Deed of Certificate (LDoC), what evidence must I provide?

The LDoC itself provides a list of evidence requirements and the government guidance provides further detail on the appropriate documents that can be provided to support the information contained in the completed certificate. These include:

A utility bill or council tax statement in your name as at 14^th February 2022 to demonstrate that the property was your principle home.
A copy of the Land Registry’s title for your leasehold property which details the current ownership and provides evidence of the last sale date. This document may also detail the last sale price.
If the above Land Registry Title does not detail the last sale price, a copy of the contract of sale, or some other formal document from your conveyancing solicitor at the time of sale, perhaps a completion statement, may be used as evidence of the price paid by you for the leasehold property.
If you are a shared ownership leaseholder, a copy of the shared ownership lease must be provided to evidence that the property is owned on that basis. In addition, the contract between yourself and the Housing Association (or other immediate landlord), or documentation arising from it, to evidence the % share owned as at 14^th February 2022, must also be provided.