A car CD player is so 1989. Why not consider an iPod adapter or an SD card slot on a head unit? I have an Audi with SD capability, and a cheap memory card can hold 5000 songs or a single telephone message from your mother-in-law. Why would you want to put up with schlepping CD's around in your car?
You can take several routes in terms of car-audio system since there are many choices nowadays:
1. Single-din cd player. Some single-din players have usb connectivity and can play flac and wav files through usb.
2. Double-din (2-din) DVD receiver.
3. Car HDD player.
4. Home Media Player with 2.5" portable HDD. You will also require an AC-DC converter to power up,
5. Single-din and double-din players/receivers can be connected with iPod/iPhone, Smartphones (Android) and Blackberry through dedicated cables/adapters.
Some also have bluetooth connectivity that can play your music/movies from the phone onto your monitor and produce the sound through your car speakers....
Your wallet simply cannot catch up with technology.