Handling fee for each period =3500*0.6%=2 1 yuan.

The principal payable in each installment =3500/24= 145.83 yuan.

Repayment amount per installment = handling fee per installment+principal payable per installment = 21+145.83 =166.83 yuan.

Total handling fee = handling fee per period *24=3500*0.6%*24=504 yuan.