Double cab dual sub setup help

I'm completely inexperienced in the field of car audio. I've never added a sub or anything. What I'm looking to do is add two 12 inch subs behind the rear seat of my 2012 doublecab with jbl and entune and factory sub.
My first question: is there enough room to run two 12 inch subs behind the seat?
My second question: if so where is the best place to get a box from? I've read about "mr marv" but I can't seem to find him.
My third question: what is a good sub and amp setup to run? Please include price if possible.
I know I'm gonna get told that replacing my head unit is the best move to make but I don't want to mess with my Bluetooth and steering wheel controls. So that will be down the road. Thanks in advance for the help.

 

Regarding "Mr Marv", you just need to create a new private message, and address it to "Mr Marv" and it should find him in the member list just fine. I am getting a single box built by him for my DC. He'd (as well as others, I'm sure) be able to tell you your options about dual 12" subs. I just went with one 10", so I have never researched a dual setup.

 

I tried creating a new private message but he doesn't appear on the list that I can see

 

Hmmm. That's odd. Should look like the attached picture here. Make sure you have a space between Mr and Marv.

 

Thank you. I searched for him again and he showed up. That's weird tho

 

If you have any woodworking experience.....
http://www.tacomaworld.com/forum/audio-video/322615-will-require-some-thinking-but-im-going-make-work.html

 

yeah those fit in nicely,
I semi based my clients build on your build

 

You may want to go chat with the people at crutchfield. You can maintain all the features you have listed with aftermarket units. Message me if you want with specific questions. I don't know much about fit but as far as wiring and what's good and what's not I can help.

 

Thanks everyone. I got ahold of the mr marv and were setting something up. He is a great guy and I'd recommend him to others