renault megane 2009 esp, abs, break system, airbag and power steering fault

A couple of days ago the sensors on my Megane started playing up, showing every possible error and completely bugging out. On top of the errors mentioned in the title, the doors kept locking and unlocking whilst I was driving. The speedometer went black, the car temperature disappeared and revs kept dropping to 0 every 10 or so seconds. Most importantly, now it always starts with 'check esp' when I get in the car. Once I start driving, all the rest of the faults come and go every few seconds.

I was told that it's a faulty ABS pump and that I will need to spend £1100 on getting that replaced. Just wanted to know if there is anything I can do or if it is the ABS pump, is that a reasonable price to pay for such a task? Thanks, any response is appreciated.