syphon it out, you can buy a syphoning kit from the garage, failing that disconnect the fuel line and pump the tank dry (turn the ignition on, put a break in the fuel line before the filter and pump it out, get a few jerry cans full of diesel, fill your car up to the brim, change the fuel filters, bleed if necessary), this should remove the majority of the petrol
The garage quoted her �350+. They told her she would have to have anew this and that
The RAC man did it for �100 with no new parts and the car has been A-OK