Epistle from landlord? (6)
I believe the answer is:
I believe this clue is a double definition.
'epistle' is the first definition.
(I've seen this before)
'landlord?' is the second definition.
(landlords let property)
'from' is the link.
(Other definitions for letter that I've seen before include "Piece of correspondence", "Written message", "Written character - landlord", "Communication via the postman", "Form of correspondence".)