Replacement windows on the Sunray Estate

[Uncomplex]

I am looking for a window company that has worked on the Sunray Estate and understands the requirements of the Dulwich Estate. Previous replacement windows that were sourced by my father do not meet the estate's requirements and so need to be replaced in order to sell the property quickly and at near face value. Any recommendations, good experiences?

[Uncomplex]

Linked to this, it would now appear that I need the help of a planning agent to get through over changes my parents made without consent. If anybody can recommend one of these that would be great.