Dads101

Hi guys I am new to the forum so please allow me a little latitude until I get the handle of the platform. I have a 525d tourer 55 plate, auto and I have a few problems which if you can help would be great. I get the following code errors
AOB5 wheel speed sensor
4o77 throttle valve
3FF2 air mass flow sensor
3F30 rail pressure sensor
3F57 charge air pressure controller
4501 exhaust gas recirculation
My car has lost power in the last couple of days and my nearest garage is talking mega money to me, he also claims to change the glow plugs may be expensive as they snap and have to be engineered out, is this true are they that fragile. Any help would be much appreciated .