(1) Instead of rescinding the agreement, the customer may, by declaration to the contractor, abate the remuneration. The ground for exclusion under section 323 (5) sentence 2 does not apply.
(2) If the party of the customer or the contractor consists of more than one person, the abatement of price may be declared only by all them or to all of them.
(3) In abating the price, the payment is to be reduced in the ratio of the value that the defect-free work would have had to its actual value at the time the contract was concluded. If required, the abatement is to be identified by way of an estimate.
(4) If the customer has paid more than the abated remuneration, the amount overpaid is to be reimbursed by the contractor. Section 346 (1) and section 347 (1) apply accordingly.