These parties may hold information about the extent to which a property is used, and by whom, which could prove valuable to a local authority in carrying out their billing functions.
Gall y partïon hyn ddal gwybodaeth am i ba raddau y defnyddir eiddo, a chan bwy, a allai fod yn werthfawr i awdurdod lleol wrth gyflawni ei swyddogaethau bilio.