The federal tax was $3,750, which means your total was actually $33,750, and with upgrade: $38,250 vs the current $38,315
I suppose you can argue there's a few percent you save because you can get credit card cashback on the upgrade but it's basically a wash.
Also of note since I see you're from SD- CA actually ran out of state rebate funding for 2019 in June. IIRC you'll still get paid but it's going to take a while (Also Trump/EPA could come and axe all the CARB stuff that California's getting this money from) so there's that to consider. They barely mailed mine and I applied four months ago, I can only imagine how long it'd take for people applying now.
Yeah I had an error but it was only $100 off.
35,400+1200=36,600
36,600-3750=32,850, not 33,750.
With 4,500 upgrade that is 37,350 vs 38,315 current.