Quick questions about CD decks

I just bought a used 2007 Corolla CE. I don't mind taking a full minute to go from 0 to 60, but I've discovered it won't play burned CDs... I managed to get one CD to play all the way through the first song but the rest of the songs only played for 10 seconds. I've pretty much decided I'll have to pony up for a new CD deck unless anyone has some tips out there....


1. Are there CD decks that have some sort of AUX line to plug my mp3 player into?

2. Do CD decks change the sound quality at all (for better or for worse)?

3. Would $50 or so for a new CD deck suffice? Are they expensive to install (like at Best Buy)?

Any comments would be great, Thanks.