Updates to story midway and at the end of the first page.
preface: I know little/nothing about cars
note: I have filled the car with gas and I have added windshield washer fluid (definitely the right hole, since it didn't work before I put the fluid in, and did work after). I haven't touched any of the other fluids in the car, and neither has anybody else. No oil changes, no maintenance, no followup safety. Nobody has touched under the hood except me.
I recently (Jan 19th) bought a 2003 Hyundai Elantra from a shop in Calgary.
They did their own safety on it (they're certified, I suppose), and it was fairly dinged up on the outside but in seemingly decent working order otherwise. They gave me a 2 month drivetrain warranty on the car so long as it wasn't serviced elsewhere.
The car ran fine for a month but in the past week the brake pedal has gotten very stiff on/off. Two days ago my wife was driving the car and the brakes seized up immediately. The check engine light went on and it was throwing two error codes (p1529 and p0734). In the past couple days the car had also been changing gears oddly, and one of those error codes is regarding the transmission slipping from 3rd to 4th, so it made sense. She was about 5 minutes away from home and then was able to drive it back without any further issues.
We arranged to bring it back to the shop in question the next day, and my wife was driving it up when, not two blocks away from home the brakes clamped down partway and she wasn't able to exceed 30 km/h. She pulled off in the nearest parking lot which also happened to have an (expensive/mediocre) shop that wouldn't charge anything to take a look at the braking system. The guys at the shop told her that there was contamination in the brake fluid and all the rubber seals / components in the brake system were done.
I called the shop where we bought the car and after waffling over the problem ("you must have have done it by accident ... do you have any enemies?? ... the guy who changed the oil on your car must have fucked up the fluid change") they told me they'd send a tow truck to pick it up.
The tow truck operator they sent never came. I got called back by the shop today and they told me I'd have to arrange for my own tow.
So, do I have any recourse? I can get the car towed, that's not the end of the world, but I don't know enough about the possible causes of brake fluid contamination to know how to fight claims of 'well, you're an idiot, you must have put gasoline in your master cylinder reservoir!'. This is an expensive repair, and I'm not sure I can afford it on top of having just bought this damned car outright.
Also note, the check engine light has since turned off.
So, how fucked am I?
I appreciate you bearing with my pleading first post