I am currently setting up a budget for a good-enough system.

Car: 2014 Mazda 3
Budget: 20-30k
Source: Spotify Premium over Bluetooth.

Two options:
1. Get an all-branded (JBL most probably) seps-amp-sub setup in one sitting, or
2. Get seps first (20k budget), then amp (no idea) then sub staggered over a few months.

Will I hear a difference in quality between options 1 and 2 considering my source? I don't think I will be upgrading to any high-end formats any time soon. I don't even have CDs anymore

Mickey's 50k Hertz package is tempting.