id try to bleed them before buying pads. see if you can get the pedal back to firm when the cars running. could be a bad master cylinder if the pedal is still mush after bleeding them. dont let the master run dry while bleeding, keep it at 1/2 full to full, no less then 1/2 to be safe. it goes fast too. some cars have 2 bleeders on the abs pump, bleed them as well if you have them.
first and fore most would be getting it running before i dropped a dime on anything else.
also check the fluid level, if its low you can get a soft pedal, as pads wear, the fluid gets lower.
