How to upgrade the performance on my ford focus?

Ok so first off let me make it clear that yeah i know this car isn't the best to upgrade or that it has much potential but honestly i'm fine with whatever boost I can get. I have a 2012 ford focus SE. That means 2.0 I4 with no turbo and everything is stock (also stock power shifter). What can I do do increase horsepower and torque? I've read about throttle body spacers, ecu chip upgrades, cool air intakes, even "superchargers" however the "superchargers are just filters that have fans built in to compress the air (do they really work?). I'm new to all of this and am willing to learn. Yeah I could have picked a better car but I'm a poor college student. I'm lucky that it has leather interior and premium wheels.

Looking for aftermarket car pieces. Where is the best?

I recently purchased a 2003 Ford Focus ZX3. I want to make it look absolutely amazing using aftermarket parts. I'm on a tight budget though, 1,000 dollars. I want to get new head lights and tail lights, a new front bumper cover, and a spoiler. What do you recommend?

Car is breaking down and I still owe money on it?

So I have a 2014 Ford Focus with the **** automatic transmission. I have problems with it and its just getting worse and worse. I'm currently on wait at the Ford dealer to fix my car for 4 months. They can't fix it for FOUR months (something about the parts being on back order for 16 weeks)! I don't think it will last four days let alone four months! I need my car for work but I'm scared I will break down and I owe more on the thing to just trade it in. I'm not sure what to do but I can't keep this car. I've only had it for 15 months and it has 18 thousand miles.

Do I need an amp for new car speakers?

I want to install new car speakers in my Ford Focus 2009. Do I need a new amp / head unit to get a nice quality sound out of these speakers? I'm interested in using the Pioneer TS-A6885R