Advice on subwoofer/amp setup for my 2023 VW GTI

I'm looking to install a 12 inch ported subwoofer in my 2023 VW GTI. However I need some advice on part information regarding the quality of brand product lines (Alpine Type S/R,JL W's, Kicker Comp C/R/VR) since it's been about a full 10 years since I last put together a system in my car and also I just am not very knowledgeable about all this.

I sorta gather how brands that used to reign supreme back then went through a steep degradation of quality control so their products now are nowhere near as solid as they used to be, ie Alpine Type R Subs, JL W Series Subs, etc.

I ran 2 12" JLw0s in a sealed ebay box for a bit for my first setup ever with some random amp then w2's which were absolutely amazing, I loved that. Those sounded so damn good, I enjoyed that setup a lot just to give some frame of reference for what I'm looking for except now I want a single ported 12" ideally cause I want to keep some room in my hatch of my GTI.

Another important reference point comes from when I heard my buddie's single 12" Alpine Type S (Sealed I think) in his old 2004 VW GTI which sounded SO good that I always wished my 2 12" JL setup was even half as good. It was most likely just a better tuned setup with actual thought and knowledge put into things better quality parts etc, what a shocker that it was so much better right?

Anyways, I listen to primarily rap, some uk garage, and metal/hardcore. I have always loved powerful, clean, loud bass with my music. I'm a total audiophile but I don't have the budget nowadays to afford

What I really would want is something like a Sundown 12" setup with a custom box tuned perfectly, like stupid low @ 24hz and I realize that my low budget won't be able to allow buying a setup that can accommodate anything close to that low of a frequency.

I have a ~$500 budget for sub, box, and amp. I have an LC2i and Knuconceptz Kolossus 4 gauge OFC amp install kit already.

Really want a powerful, reliable, clean sounding setup that would compliment the music genres I enjoy listening to the most that sounds the best at primarily the lower range of frequencies but still performs decent in higher frequencies. Most important is clean, impressive sounding low end.

I really wish I knew someone that could build me a custom enclosure for a good price but unfortunately I don't think a custom enclosure is in the cards which is why I'm considering only prefab stuff...

I've been thinking of:

$360 Kicker Solo Baric L7S passive 2ohm 750w RMS + box

$260 Kicker Comp R passive 2ohm 500w RMS + box

$280 Kicker Solo Baric L7T passive 2ohm 600w RMS + box

~$200 Alpine Type R 2ohm just the driver and find some prefab somewhere online that would do it justice.

And finally the best one, my top pick I think:

$280 Sundown SA-12 D4 Classic dual 4ohm 750w RMS - Only possibly issue is that 4ohm might not suit my needs but this thing might slap so hard it might not even matter lol. I don't think I'd be able to get an enclosure that would do this thing justice at all, at least not for a year or so when I can work on paying for a custom box for it. It's just hard to justify paying the equal cost of the sub itself on an enclosure at the moment but for a Sundown it would be worth it down the line.

For all of those subs though I'm totally clueless as to what amps I should run...

If you made it through this flood of text I salute you and would GREATLY appreciate any help in pointing me in the right direction. I want to get everything installed this month so I want easily accessible parts. Thanks!!!

EDIT: Not sure how in all the hours I spent researching this stuff I missed this entire wormhole online of custom built enclosures I'm stumbling upon right now. There are a ton of them for sale around $200 for the higher tier subs I'm interested in...

Ported Sundown SA-12 box built to perfect specs tuned @ 33hz for $250: https://lifeafterbass.shop/products/lab-2-00-ft-3-ported-mdf-enclosure-box-for-sundown-audio-sa12-subwoofer

Here's another one for about $180 but it's not completed: https://www.ebay.com/itm/115067061096?chn=ps&mkevt=1&mkcid=28&srsltid=AR57-fCHnRay2K65ig1SvxncFo56gfiPe1s8nUaCy_pENt3PrJhXIAG-ob0

I should mention that at this point I'm beginning to realize that I wouldn't be able to fit an SA-12 in the trunk of my hatchback without seriously compromising the space back there given how huge the drivers themselves are as well as how huge the ported enclosures need to be. Not to mention that they are freaking heavy and I'd be adding about 100 lbs to my manual turbocharged hot hatch which isn't exactly ideal but I do know if I made that compromise I would not be complaining from how much it bumps lol. Idk

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