PZL8erade

my brother has a 99TL stock bose deck with navi. he has aftermarket speakers and subs already installed, but he wants a deck so he can connect his ipod. He doesnt really care too much about the deck so somethin in the $100 range is fine. I went to best buy to get an estimation for install and they were sayin that I have to buy an extra set of cables insteal (not the install kit cables) but cables to bypass/override the bose amp and were tryin to charge a total of like 100 for the total price of the install.

this that something i need to have bypassed or are they just tryin to pull a quick one?