Like the title says, I'm a noob to car audio but I've been researching for a week or two, so I have a general idea of what I want. I'm building a budget system, ~$600 like so many other people. I'm looking for a good balance of SQ/SPL. I will be installing everything myself with help from the internet, of course.

I drive a Subaru Impreza 2007 sedan, for reference. Everything audio is stock right now. I listen to a bit of everything, but a majority of rap/dubstep/hiphop with some rock.

I picked up a set of Alpine Type R 10"s (good condition, no cracks, I tested them before i bought them) in a ported box, powered by a Diamond Audio D3 600.1 amp. A question I've been having is, how can I tell if the box is tuned for the subs? I should probably measure the box to find out of its the right sq. footage correct?

There are SO many threads about here comparing budget 6.5" comps but I can't find a good definite answer. I think $150-$200 is a good amount for my comps. I'm looking at the Monster Audio CK6 and the CTX65CSs, unless someone can convince me otherwise. I've heard the HAT Imagines are good too. The depth is important, it can't be more than 2.75. Is there a reason I should go with any over the others or is it just preference? Because I have searched for reviews and comparisons and they just go in every direction.

Since my sub is already powered, how should I power my comps? Should I get a 4 channel or a 2 channel? Right now looking at this because I've heard good things about it:
NEW MB QUART ONX4.80 640W 4 Channel Car Amplifier Amp | eBay

But I've been seeing things about the Massive NX4 as well.

Does a good budget bluetooth/SQ deck exist? This is something I am definitely clueless about. Good SQ, iPhone compatible. $150ish, any fan favorites?

What do I need to wire all this up? Doors to amp, doors to deck, How will I wire the 2 separate amps? What gauge should I use?

SOUNDPROOFING/DAMPENING/DEADENING(however you want to call it)
I was going to do peel and seal.. but I think it would be a smart investment to protect my car and use a car application specific product, Raamat looks like a good product price. I'm primarily concerned about my doors and my trunk, because that's where the audio will be.

About how much sq. footage would I need to do a decent job/coverage on these locations? Will I need to cover every square inch, or can I do spot application? Or is there a different product that runs cheaply that people would recommend? Is there anything else I'll need to seal the components?

What would you all recommend with what I'm trying to build and why? I would like to keep this all relatively simple if at all possible..

Again, I am doing all of this myself. I'm a 21 year old college student so I am on a budget but I'm also willing and wanting to learn how to do all of this.
Thank you all SO MUCH for the help/advice in advance I'm anxious to finally have everything and to start the installation.!!