vendor help

what would you?

i got a quote from a vendor and now that we are close to finalizing, they’ve increased the price by $500 saying that their software had the number incorrect. to be fair to them, i did go back and see that i was charged less than their advertised price, but they made a mistake and i feel like they should honor it. i asked and they brought it down by $250 but i’m still paying more than what i was quoted. this is a vendor i really like, has 5 stars, and comes highly recommended, but idk this put a bad taste in my mouth. would you still book?