s 521 Starting expenditure
(1) This section gives the starting expenditure attributable to a dwelling-house for the purposes of section 517. (2) If the person to or on whom the balancing allowance or balancing charge falls to be made is the person who incurred the qualifying expenditure attributable to the dwelling-house, that expenditure is the starting expenditure. (3) Otherwise, the starting expenditure is the residue of qualifying expenditure attributable to the dwelling-house at the beginning of the relevant period of ownership. (4) If section 528 (treatment of demolition costs) applies, the starting expenditure is increased by an amount equal to the net cost of the demolition.