10 commandments for buying an HDTV at a "big box" store

There are all kinds of reasons to buy an HDTV at a big box electronics store. Maybe you found a really good price in one of their ads. Maybe you have a family member who's suspicious about getting a big-ticket item over the web. It doesn't matter. The point is, you're walking through the door with the intent of getting an HDTV. These ten commandments will help you get the best deal with fuss. If you have friends or family members who want to get an HDTV but don't read Sound + Vision, print out these rules and staple them to their coat when they go to one of the large chains.

I. Thou shalt know what thou wants to get.
This is the first and most important rule. You're making a big purchase, and you should know exactly what you're looking for. Considering HDTV prices range from $500 to $5,000 even in brick and mortar chains, you need to walk through those doors with some specific decisions already made: what type of screen you want, what size of screen you want, and how much you want to pay. Ideally, you should already have a model in mind. II. Thou shalt know what is available.
If you have a specific model in mind, check to see if the store actually carries it before you enter. Small variations in models can make a big difference, whether it's a different image processor or a missing feature. You'll save a lot of time and frustration by checking the web and calling ahead to make sure the HDTV you want is ready to be loaded into your car. III. Thou shalt not fall victim to fine print.
Sales and discounts are appealing, but they sometimes come with a catch. Just because a price is advertised in big, bright red letters, doesn't mean that's the price that will end up on your receipt. Make sure the final price doesn't involve a rebate (which takes weeks to process) or additional products or services you're required to buy. Combined with the 2nd commandment, this is a vital step in avoiding the dreaded bait and switch. IV. Thou shalt ask for, demand, and receive service.
There is no such thing as an HDTV vending machine (yet), which means your rather substantial purchase is going to require the involvement of one of the store's associates. Make it clear that you're interested in purchasing an HDTV, and they should be able to assist you in checking the stock (don't accept floor or refurbished models), verifying discounts, and actually schlepping the screen out to your car (or arranging delivery). V. Thou shalt not let the sales staff bear false witness.
Despite what the ads might say, the staff at big box chains generally doesn't consist of home theater professionals with extensive experience. There's a real chance they might not know any more about the HDTVs they're selling than the information on the store's web site. That said, take any technical information they give you with an entire mountain of salt. Refer to the first 3 commandments, and know that as long as you've done your research beforehand, you probably know a little more about the technical issues of the product you're buying than they do. VI. Thou shalt not let the screens bear false witness.
Do not judge an HDTV by how it looks in the store. Unless your home theater room has fluorescent lights 30 feet above your head, your experience at home will be drastically different. More importantly, the display settings are tweaked to make the pictures "pop," at the expense of color accuracy and picture quality. Plus, you often won't be able to look behind the screen to verify that it's hooked up to the source via HDMI or component cables. Read performance tests conducted in controlled environments and remember that you'll have an entire suite of controls to tweak the picture to your liking when you get the HDTV home. VII. Thou shalt not covet thy store's cables and accessories.
Unfortunately, your new HDTV probably doesn't come with any HDMI cables, and if you get a Blu-ray Disc player, that probably won't have a cable either. It's a simple way to reduce costs for manufacturers, and offers a great opportunity for outrageous mark-up in large brick and mortar stores. Their cables can be ridiculously priced, with "generic" cables retailing $20 if you're very lucky, and brand-name cables easily reaching $100. Online retailers like Amazon, Newegg, and Monoprice, on the other hand, have functional cables that cost as little as $5. They won't cut it for large, complex installations, but you probably won't see any difference between a generic and a brand-name cable in a small home theater. 
VIII. Thou shalt not covet thy store's technical support services.
Once again, refer to the 5th commandment. Unless your home theater is very complicated, you can probably do all the set-up yourself. Run a cable from your source (Blu-ray player, cable box) to your HDTV, plug everything into the power, and turn it on. Even more complex and finicky set-up maneuvers, like configuring networked features and wall-mounting your screen, come with direct and fairly simple instructions. Even correcting the picture is a relatively simple process thanks to the availability of affordable calibration discs. IX. Thou shalt not covet thy store's extended warranty.
Store-bought extended warranties are every bit as overpriced as cables and set-up services. Retailer extended warranties have a long history of complaints; replacements aren't given or aren't worth nearly as much as they should be, repairs aren't reliably performed, or HDTVs get caught in the black hole between the store and the repair center. Most HDTVs come with a 1-year manufacturer's warranty anyway, so you're at least covered for that long. X. Thou shalt be willing to haggle (and judiciously ignore commandments 7-9). 
Let's be blunt: the larger electronics stores make a significant amount of their profit from service plans, cables, and installation services. More importantly, the sales staff tends to be evaluated more on what services and accessories they can sell than what actual electronics they can move out the door. Don't be afraid to try and haggle with the salesman on the price of the HDTV or on putting together a package deal in exchange for purchasing those extra services. If you can get a $200 Blu-ray Disc player thrown in for getting a $150 installation plan, you come out ahead. If you can get them to shave $100 off the price of the HDTV for a $60 cable, you come out ahead. Just remember your own bottom line, and work towards that deal. And don't be discouraged if you get shot down. 

-Will Greenwald