I want to get a floor plan for one small room

Design details: I would like to find someone who can come and measure up a small room I have and then provide a clear and accurate floor plan (including height, width etc). I will then use this floor plan to order some wardrobes. The measurements need to be exact and take into account the slight slope in the ceiling. You will need to be prepared to visit and take measurements. I am based in Sutton, London (SM2). It is a tiny room (to be used as a walk-in cupboard) - see attached for dimensions. I just need someone to add in the exact heights and reflect the slants so that I can take the measurements to IKEA and get some wardrobes designed!