258 yuan. The monthly repayment amount of the loan needs to be calculated by multiplying the total loan amount by the number of loan periods and then multiplying the loan interest rate. The second-hand car loan of 30,000 yuan is based on the national loan interest rate of 3.45%, and the term of the 36th loan is three years. The calculated monthly payment is 3000 times 3.45% times 3 divided by 12, which is equal to 258 yuan.