I have an opportunity to buy this and it was a floor model... He is selling it for $400 and it still has an alpine 90 day warranty... Do I need to buy a cd changer to listen to cd's? Will I need an external amp? What else might I need and is this a quality unit? Is the price decent...

I have a cda-9835 right now and can move that to my beater car if this is a good unit...