(1)

(a) Where any capital expenditure has been incurred on the construction of a building or structure in respect of which an allowance has been made under this Chapter, and any of the following events occurs -

(i) the relevant interest in the building or structure is sold,

(ii) that interest, being a leasehold interest, comes to an end otherwise than on the person entitled to the leasehold interest acquiring the interest which is reversionary on the leasehold interest,

(iii) the building or structure is demolished or destroyed or, without being demolished or destroyed, ceases altogether to be used, or

(iv) subject to subsection (2), where consideration (other than rent or an amount treated or, as respects consideration received on or after the 26th day of March, 1997, partly treated as rent under section 98) is received by the person entitled to the relevant interest in respect of an interest which is subject to that relevant interest,