I have a 2015 honda fit, so not a lot of cargo space.
Stock alt, double ott wiring for sub amp, 4ga for mains, 100ah AGM battery mounted beside the sub amp, Minidsp 2x4HD. That stuff is mounted under a false floor/in the spare tire well, so it just the sub box was taken.
For now I am just shopping for new subs, and will build a box around them. Later on I would like to get a different sub amp, but for now I have 1800 watts to use and I'd prefer to spend under $450 and have been looking at the Seven, Dayton HO or UM, Massive Hippoxl, Death row, Xcon and sundowns.
I'll likely go with a pair of 12's, but was thinking about a single dayton ho 18" in a sealed 4cuft box for something simple and clean.
I probably won't have $$ till next month to buy anything, but I do have 4 dayton ultimax 15's in my living room, so one of them may end up in my car for a little bit. lol