Hindsight being 20/20 , if I had to do the retrofit again , I would have gone ebay for the CIC radio, controller, screen and cable.In particular a shop called straight six auto, u can reach out to them on Instagram , good prices.
Next is the interior trim pieces. The climate control bezel etc , straight to dealer. They are surprisingly not expensive.
The only thing I would buy locally would be the double hump dash.For that try MD house, there you can also buy old wiring harness to cobble together ur own harness
From my experience some of these local breakers are extortionist in the pricing.
One more thing to note , you absolutely need to get a CIC unit from a very late model car for the retrofit to work.The later software has a weakness/backdoor that you exploit to virginize the unit
Good luck