Black Friday car audio systems?

Hi pretty random but I was wondering if anyone knew any good places that have awesome deals either Black Friday or any other time for car speaker systems. Websites are fine and I'm in the boston area.

1 sealed and 1 ported sub, powered by 2 Amps. Would it work? A guy in a local shop said they have tried it and it sounded bad when combined.?

Yes, the ratings on the cord are the maximum that it can handle.

The Radio is the right voltage, and only needs about 0.1 A, which is safely under the cables rating

Can I put this stereo in my car?

I'm thinking about buying a 2000 Lincoln Navigator. The stereo that came with it was already pretty good. I recently rode in a 2005 Ford Escape Limited. That had a Mach 300 audio system. I really liked this stereo. Could I put this stereo in a Navigator? Could I hook it up to the steering wheel controls?

do I need a isolator if so how many amp have to batteries do my battery in the front charge the one in the back?