England & Wales: http://www.voa.gov.uk/
Scotland: http://www.saa.gov.uk/
Northern Ireland: http://www.dfpni.gov.uk/

Check our credential

Royal Institution of Chartered Surveyors: http://www.rics.org/uk
Institute of Revenues Rating and Valuation: http://www.irrv.net/homenew/index.php

Check Case Law

Avoidance discussion paper: https://www.gov.uk/government/consultations/business-rates-avoidance-discussion-paper

Code of Practice

RICS/IRRV/RSA code of practice: http://www.rics.org/Global/Rating_consultancy_4th_edition_PGguidance_2017.pdf