Since you are looking at a 2021 model , here are a few specific things to keep in mind for this particular year: Why the 2021 is a Great Choice The Engine: The 2021 M40i features the B58 engine paired with a 48V mild-hybrid system . This setup provides smooth auto start-stop transitions and an extra boost of torque for better efficiency and punchy acceleration. BMW Factor optional Equipment: Drivers Assistance Professional Pkg., Executive Pkg., Harmon Kardon Surround Sound, and Wireless Charging. Tech Standards: By 2021, Android Auto and Apple CarPlay were standard and wireless, which is a major convenience over older models. iDrive 7: This model year uses one of BMW's most stable and user-friendly infotainment systems, featuring a mix of physical buttons and a responsive touchscreen. Comparison Tip If you are comparing this to other SUVs, the X3 M40i generally holds its value better than the base 30i model because of its desirability among enthusiasts. Would you like me to help you find the current market value for a 2021 X3 M40i in your area to see if the price is fair?