Leasehold flats as with all residential properties including require a HIP before they can be marketed. The elements in the Leasehold HIP for flats include an a copy of the lease for your flat plus any Deeds of Variation and the completion of a Property Information Questionnaire (PIQ) .
The PIQ, which is still needed if you have a share of freehold, requires you to answer about 10 questions including what is the name of the person to whom you pay the ground rent, the amount of the ground rent and the current annual service charge, information on any proposed major works to the block and some basic questions about your lease.
Most HIP providers do not wait for you to provide them with a copy of your lease but rather obtain a copy from the Land Registry. Your Landlord or managing agent does not normally have a copy of your lease.
If you are thinking of selling your flat it is in your interest to keep documents relating to the management of the block so that they are available to answer enquiries once you do find a buyer even though they may not be needed in the HIP.