Is the contractor entitled to claim an increase in the previously agreed-upon construction fee, even though the four-year delay in completing the construction was due to him, and this also caused harm to the owner as a result of the rise in finishing material prices?

The party to an agreement cannot back out of the agreement or demand an additional sum as long as the delay in construction was due to them. They must fulfill the contract, in accordance with the Almighty's saying: "O you who have believed, fulfill [all] contracts."

However, if the delay was due to unforeseen circumstances beyond their control, the matter should be referred to the judiciary. The judge has the right to modify the rights and obligations to distribute the loss between both parties, or to annul the contract with fair compensation for the aggrieved party, taking into account the opinion of experts. The judge may also grant a grace period to the obligated party if the unforeseen cause is likely to disappear soon and the other party has not suffered significant harm.