1. Coolant bleeder screws
Stainless Steel coolant Bleed screw replacement kit- Alfa Romeo Giulia/Stelvio 2.9L/2.0L/1.8L -Alfissimo International
shop.alfissimo.com
2. 5/16 (8mm) replacement coolant lines that come from both of the reservoirs.
Is this pre/post refresh thing? I've actually not seen this before. Does anyone have a suggested replacement part that is higher quality?
3. New relays for various items throughout the car.
Panasonic CM1A-R-12V seems to be a favored swap replacement for from OEM relays. I got mine not at amazon but either ebay or other online seller.
4. Knowledge that if you throw codes within the first few weeks it is probably due to a low state of charge on your battery.
The above happened to me inside 3 weeks. Like yourself I bought my car off lease with only 25K miles. You'll get a Check Engine Light where auto start/stop is disabled. You won't be able to change drive modes. The cause was not a bad battery but the battery posts having corrosion build up requiring just a cleaning. this youtube video shows both cleaning battery terminals instructions and shows the locations of the easily accessible relays.
The video above shows a "method" of clearing Check Engine codes however it's overly complicated. This video shows the quicker/easier method
You can even try it without the battery quick disconnect before going through that step.
5. Knowledge of how to reset the codes if you do run in to them.
The above shows how to clear dash codes however it's also advisable at minimum if you don't already have one, grab yourself an OBD2 scanner. The ability to do more than read codes requires a securty bypass tool. In theory you'd need this along with some other connectivity tools if for examply you change your own oil and wish to clear the maintenance warning.
Alfissimo SGW Bypass (Security Gateway bypass)- Alfa Romeo Giulia/Stelvio +
I was shopping for my 2.0 last year this time including looking at Veloce/T-Sport's that's a very good price. See if you can't get the actual service records from the local dealer who serviced this car. It will be helpful to know what has and hasn't been done at the 20K and 30K maintenance. You're gonna be smiling so much, before you know it you're at 40K
I'll second the suggestion for the GoPedal Plus, the throttle response varies quite significantly between the D, N and A drive modes and the GoPedal allows you to individualize the throttle to your preference. I prefer a single setting for 99% of my daily driving, Sport 3, which I would call N+/D- in comparison to the stock throttle mappings. I found A mode unusable the stock throttle response was so slow, now I use it for all my residential driving. Plug and play install takes 15-20 minutes top
https://madnessgopedal.com/gopedal-plus-by-madness