Buy EQE SUV used, what to look for?

Hi all, I had the pleasure of driving an EQE 43 in the AMG version a few weeks. So far I still have a burner, a Kia Stinger GT. I find the EQE SUV great, especially in order to make comfortable tours with the family. I plan to get the starting next year. So far I had the focus on the Tesla model Y, but the EQE SUV was ahead by lengths, but price-wise as a new vehicle outside of my reasonable budget. a dealer after used EQE SUV, important to me MBUX and the hyperscreen, I also find the AMG package nice. New price is the around 130k, I hope for a used as a good compromise for the 50/60k purchase price. What I have seen so far, the dealers demand rather so 70/80k for a well equipped. Do you have experiences what is still there in negotiating scope ? Or that they buy my car at a good price ? In addition, on what should I a real ? On a 350 or with + or a 43 ? The leasing rates for new ones are currently underground, so it is more worth buying a used one for me. I drive so 15 TKM a year. Thanks for your opinion