Yes, verbal contracts are contracts BUT I'm betting there's NO way anyone would verbally AGREE to a $9K increase in the price !!! The fallback is ,if the store said 'yes,you did', is the WRITTEN contract.
Also, since this is financed, THAT paperwork must have a LOT of 'details' ( like purchase price....). It'd be interesting to know if the FINANCE company agreed to the $9K increase !! While 9k ain't a lot of coins these days,,they might not.... Also as financing is involved, there's a 3rd party who has a HUGE stake in the deal....
Honestly have a 'stranger' read the 'sales agreement' or 'contract'..see if they see anything about the 'price'.
Heck, you could scan and post here ( blackout 'redact' ,any personal stuff,even price.
Hopefully ,back of the contract doesn't have a 'section 15b...price adjustment...blaa,blaa,blaa.......'