Retailers make little on TVs, lots on overpriced cables, warranties, etc.
Extended Warranties
The perennial favorite. If you don't use them, they're 100 percent profit for the store. Think of them like any other insurance. For flat panel TVs, they're not generally worth it. Both plasma and LCD TVs are extremely reliable.
Cables
Sad to say, you're not going to get the cables you need in the TV box. You will need HDMI cables (or component, but HDMI is that little bit better, and a lot easier).
What you don't need is to spend a lot of money. There are only two states possible with an HDMI cable: it works, or it doesn't. If you see a picture, and it looks good, then you are getting the best picture possible. If you don't see a picture, or it's messed up with speckles, then the cable is defective and you should return it.
But $100 HDMI cables do not offer any additional performance over a $5 HDMI cable.
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