(1) The hirer under a hire-purchase agreement or the buyer under a conditional sale agreement may give notice in writing to the owner or seller of his intention to complete the purchase of the goods by paying or tendering to the owner or seller on a specified day the net balance due under the agreement, and having given such notice may complete the purchase accordingly on the day specified.

(2) For the purposes of subsection (1) of this section, the net balance due is the hire-purchase price or the total purchase price, as the case may be, originally payable under the agreement less any amounts paid or provided, whether by cash or by other consideration, by or on behalf of the hirer or buyer under the agreement.

(3) The rights conferred on the hirer or buyer by this section may be exercised by him-

(a) at any time during the continuance of the agreement; or

(b) within twenty-eight days after the owner has taken possession of the goods (during which period the owner shall not be entitled to dispose of the goods) upon paying or tendering to the owner in addition to the net balance due-

(i) the reasonable costs incurred by the owner in and incidental to taking possession of the goods; and

(ii) any amount properly expended by the owner on the storage, repair or maintenance of the goods.