Bring the location, the frontage you believe you have, and any paper you already trust: mutation, a survey, a photograph of the approach. Do not commission a glossy scheme before the conversation.
We will ask what you want to keep. Some families want a building they can live in. Some want a commercial floor with a serious tenant. Those are different drawings, and they should not be blended to make a taller number.
If the plot is wrong for the way Razz builds, we will say so in that meeting. A polite no is cheaper than a year of drawings.