I own a 1 bed flat in London. It is the middle flat of 3 in a converted Victorian terrace. My bathroom is an extension over my downstairs neighbour's bathroom and has a flat roof. My upstairs neighbour has submitted a planning application for their own bathroom extension over my bathroom, building on my flat roof.
I don't have an issue in principal, but want to make sure I agree with my eyes open. What information should I be asking for?