Article 7:752 Dutch Civil Code, Book 7

Paragraph 1

If the price was not determined when the contract was concluded or only an indicative price was determined, the client owes a reasonable price. In determining the price, account is taken of the prices usually stipulated by the contractor at the time the contract was concluded and of the expectations raised by the contractor with regard to the probable price.

Paragraph 2

If an indicative price was determined, this indicative price may not be exceeded by more than 10%, unless the contractor has warned the client as early as possible of the likelihood of a further overrun, in order to give the client the opportunity to limit or simplify the work after all. The contractor must cooperate in such limitation or simplification within reasonable limits.

Paragraph 3

Paragraph 2 applies mutatis mutandis to contracts for work in which the price has been made dependent on the time estimated in the contract for carrying out the work.