asyncritus

Good Day, I am very new to auto sound system. I am planning to get my sedan a sound setup, I would like to seek your expertise what is the best sound performance Ifor spl I'm choosing between one (1) T2 12" subwoofer 4 ohm and one (1) RF t1000.1bd amp. or two (2) P3 12" 4 ohm and same amp (t1000.1bd)? I have a very limited trunk space in my camry. If you suggest to get two (2) P3 12", according to the data sheet of that sub I need 1.79 cu. ft. for each sub, when I'm going to make my own enclosure do I need to double that size so it will be 1.79 cu. ft. x 2 for my enclosure? Thank you in advance.