4. Residential property fully subject to municipal rates.
A residential property shall not, for the purposes of section 16(1), be regarded as a relevant residential property where the property is a property which -
(a) is wholly used as a dwelling (other than a dwelling that forms part of a mixed hereditament within the meaning of the Local Government (Financial Provisions) Act 1978), and
(b) in respect of which municipal rates (within the meaning of the Valuation Act 2001) are payable.