Is it permissible to make a second, amended bid for the purchase prices of machinery, after signing a contract that includes invalid conditions such as delay penalties, knowing that the first bid was made before signing the contract?

Appraisals that do not affect the invalidation of conditions, whether before or after the contract, do not differ. As for the delay penalties imposed on the supplier for late delivery, there is no objection to them, because they are penal clauses related to the execution of works. This differs from a penal clause related to late debt payment, which is prohibited.