Section 24. The court may award costs in the suit for redemption to either party; but if suit is brought without previous tender and it is found that the condition of the mortgage has not been performed, the plaintiff shall pay costs of suit, unless the court finds that the defendant has unreasonably refused or neglected, when requested, to render a just and true account of the money due upon the mortgage and of rents and profits and amounts paid for taxes, repairs, improvements and other necessary expenses, or that he otherwise by his default prevented the plaintiff from performing or tendering performance of the condition before commencement of suit.