The Minnesota DMV is so petty. Claimed I owe taxes on vehicle cause my reported purchase price was $600 under the "fair value" for the vehicle

I purchased a vehicle for $2900 in December. The only issue was that the car needed a window regulator for one of the back seats. However, the DMV claimed that the vehicle is actually worth $3500 and the only way to get out of paying $250 in taxes is to bring in repair estimates. So I went to the dealership to get a quote for $700 to replace the window regulator and submitted it. Hopefully that repair estimate will stop the DMV from holding up my title collect sales tax over a $600 discrepancy. I also recently decided the car was not for me and am trying to sell it to carmax for a few hundred under what I paid for it, but until I get the title, I can't sell.