Can an owner list a rented room?

Yes, if you own a 3-room or bigger flat, you can sublet your bedroom(s) without prior HDB approval. You must register the subletting with HDB within 7 days, and the total number of occupiers (including owners and subtenants) cannot exceed 6 persons. Owners of 1 and 2-room flats are not allowed to sublet their bedrooms.