If you want to say that 20 years is cost-effective, the less the loan period, the less the interest. But whether 10 (or 20) or 20 (or 30) is suitable for you depends on your own income or investment plan: the total interest paid to the bank in 10 (or 20) is less, but the monthly loan amount is 20 (or 30).

If your income is under pressure after paying the monthly payment, or you want to leave some money for other purposes, then choose 20 years (or 30 years) to repay, so the repayment pressure will be less. You should make a decision according to your own economic situation. The best choice is different in different situations.

Loan principal: 730,000 yuan

Loan term: 20 years (240 months)

Calculated by commercial loan and equal principal and interest.

Annual interest rate: 5.78%(6.8% is 8.5 fold), (monthly interest rate is 4.8 16666667‰).

Monthly payment: 5 137.72 yuan.

Total interest: 503,052.79 yuan?

Loan term: 30 years (360 months)

Monthly payment: 4274 yuan

Total interest: 80864 1.54 yuan.