The handling fee for the installment of Xiaoyuhua is calculated according to the remaining principal, and the penalty is the remaining principal multiplied by a certain proportion. If the total installment amount is 1 0,000 yuan, which has been returned to 300 yuan, and the remaining 700 yuan has not been returned, the installment is cancelled at this time, and the liquidated damages to be paid are the remaining principal 700 yuan × 10% = 70 yuan.