We currently rent half of a house and the landlords live in the other half. We’ve been wondering about asking if they are interesting in selling up, both halves (there are reasons why they might be interested). The house was originally one, and still has internal doors between the two at both ground floor and first floor, so all you’d need to do is unlock those and turn one kitchen into a utility room. It’s on the same electric and water but it’s separate for council tax. Would we need council permission etc to do this? Planning permission?