Regional Hyundai

You be the judge. 10 days ago went in to look at making a deal decided to wait. Went back today and salesman and I made a deal and I allowed to pull credit and things were going good, after 20min guy comes and tells me my car devalued $3,000 in 10 days. GM comes and says when I make a deal with salesman it has to be approved by him. Buying cars as much as I do, when a salesman says let's finish paperwork and pull credit it's a pretty done deal, minus financing. So advice, make sure GM has said yes it's ok before you know it's a done deal.