what is the cost to get the abs brake system repaired

Please describe in a little more detail , WHY you were told you need to fix your anti-lock brakes? WHAT happens 'when I have to brake fast in traffic'? When you brake 'fast' the ABS is meant to prevent wheel lock-up , this will usually make a bit of a 'hammering' sound and feeling with the brake pedal. THIS IS NORMAL>

it sounds like you have an abs light coming on. If that is true then you need a shop to look into the codes and trace affected circuits. then if you want to repair it yourself you will know what to replace. Generally speaking you should be looking at $125 to $160 . at a reputable shop.