Your selling price probably already has incentives. Try to get 20-22% off MSRP prior to any incentives. Consider MSDs to lower your MF.
Here is a deal on a similar X1 (Msport 47k MSRP) I’ve got about a month ago.
My lease was also for 15k miles and it was a true $0 down $369 monthly. I say you can do better, just push the dealer a bit more and lower the selling price.
