How do people go about proving water efficiency in QLD? Water charging | Residential Tenancies Authority Water charging fact sheet | Residential Tenancies Authority Does your property manager insist on a 'certificate of water efficiency' from a plumber before they charge for water? Or do you plan on proving water efficiency another way (through receipts, packaging, instruction manuals and/or build dates (when only WELS 3 star are the only appliances available)) if required? I ask because my interpretation of those links tell me the certificate is 'good idea', but not mandatory, and that the other ways are fine. I can understand in the event of a dispute you'll wish you had one but it's not a must have to begin charging (and a waste of money if there is never a dispute on the properties water efficiency and the tenant pays just fine). Not to mention all it takes is a tenant to remove one washer and the whole property becomes non-compliant... to have a check done every tenancy seems overkill as they run at $150-200 minimum and sometimes up to $300 when they 'find something'.