The tender, payment, or acceptance of the award shall not prevent either party from prosecuting the appeal. If the amount awarded by the assessors is less than that found by the final judgment, the person seeking condemnation shall be bound to pay the sum so finally adjudged in order to retain the property or interest. If the amount of the final judgment is less than that awarded by the assessors, the owner shall be bound to refund any excess paid to or received by him; and a judgment for such excess shall be rendered against him to be collected by levy as in other cases.