Help! Clutch and brake won't depress car won't start

I just purchased an 06 Aveo TODAY and it won't start. It drove fine on the test drive. My last car was an air cooled vw and sooo much simpler. I have no clue where to start with this car. I've never worked on anything but my old bug. The clutch pressure was in and out. It got stuck to the floor I tapped it and when it came back the car seemed to jerk into gear. It would shift fine then the clutch would stick then pop into gear. This happened a couple of times until I got to my house and parked. The clutch and brake won't press down at all now. I checked the brake fluid it is almost at max but the cap is so tight I can't get it off. Clutch? Clutch master cylinder? Any ideas? Will this be a costly repair?

For the brake pedal, you wont be able to depress when the car is off anyway.

The fact that the clutch got stuck in the down position and didnt come up on its own, and now that it stays in the up position and wont let you depress it, leads to an issue with the master cylinder and/or the clutch hydraulics.

I would check the amount of fluid you have in your cluth/brake fluid reservoir and make sure it is at the correct level. Then I would crack the bleed screw on the slave cylinder open (to relieve any pressure in the hydraulic system) and then see if you can depress the clutch. (do this as a test; keeping the bleed valve open and depressing the clutch will lead to air entering the closed system; you will need to fully bleed aftewords.)

I am guessing you didn't buy it at a dealership? no warranty?

This is most likely a hydraulic issue as already stated. What the fix is? Since it affect both systems, is hare to say. I could guess frozen hydraulic fluid, since that is really the only thing the two systems share. (beyond the reservoir). Is it cold out right now?

How far did you drive before the failure? I would say look under the dash for any broken mechanics / blockages in the pedal assembly just to be sure that it is not something along those lines.