if you have more than one reasonm(grounds) for refusing – your decision needs to cover each and every one
They cant appeal your decision unless thy know your reasons for refusing.
Re commerciality – have you asked for the gas/electric certificates/energy certificates and the info for tenants pck they are legally required to have sight of befor a tenancy can commence? they are a legal requirement and likelt that if they have lived there 50+ years., there would have been some electrical updates required to get it certified as ok to let.
