Easy, ask what they charge to install up front before buying anything, then compare to other shops to see if they're price is in line. Shops here give lifetime warranty on installation/wiring. Look at what gear they have in the store, then inquire about purchasing and ask whats the best price they can do compared to online, if they can come within a 20 to 30 bucks then I say support your local store by buying from them! Mention that you would rather buy it from them since they are going to install it and be cool with them and see how they react. If they don't come down or get close to online prices then tell them you can't justify spending x amount over online pricing, then go buy it online and bring it back to the shop and have them install it for the price they quoted you. The installers will install it the same as they have to honor the installation warranty and there should be no price difference. Keep in mind you can spend a lot of money for installations, 50 - 70 for front speakers another 50 - 70 for rears, 100 for amps, 125 for HU installs, and if you get into sound deadening that can get VERY expensive. Install it yourself if at all possible and save they money to pay for good gear. If your not comfortable then just find a good shop that is cool with a good rep and work with them. They're in business to make money and if it's a good shop they'll install whatever you bring. They make more money on installation than they do selling equipment and many shops don't keep a lot of good inventory.
