I need planning and listed building consent for some external/internal alterations.

Design details: I have an 18th century listed building in a conservation area. There is a 2 storey flat roof extension at the back that was built around 1960s/1970s. The ground floor at the front is a shop with A3 consent. There is a maisonette above the shop. I wish to seek planning and listed building consent to put an entrance hall/stairway at the front to the maisonette above using part of the shop. At the moment, access to the maisonette is from the rear through the flat roof extension. I also wish to re-locate the stairway in the extension.
Ideas for the visual style: Plans need to comply with the local authority requirements.
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