Brake disc corrosion

[mihangel]

Hello I am looking to buy a used Audi. The car I am interested in had a brand new mot and 145 point check completed the day before my test drive.

After test driving I was looking the car over and noticed the front disc had corroded and a chunk missing. should this have been picked up by the 145 point check or even failed it’s MOT?

Thanks for looking

[mihangel]

46k they replaced the back discs and pads in the 145 point check but not the fronts. Maybe an expensive part and job?