I have worked with different insurance companies over the years....
If you have an existing DASK insurance policy, and you wish to renew the same policy with the same broker, then they can give you a quotation using the information that you gave them from the previous year. All necessary details are saved and then the new policy amount is calculated.
If you want a new quotation from a broker that you haven't used before, then you would need to provide a photocopy of your title deed, as well as the square meterage of your property. From that the new broker will be able to get a quotation of your DASK policy.
Nikkie