Wagons are not hot sellers but there isn’t anywhere near the same inventory so they still sell out. As with any MB your best bets are to focus on ensuring you are paying at the buy rate, no MF mark ups and that you are clear on discount vs rebates. From there it’s just a game of which dealer will give you the best discount.
I tried to hunt down an e400 as my c class ends soon and I couldn’t come anywhere near a decent deal. I turned to Volvo because I have a-plan and the conquest offer this month is 5k if you have a competing vehicle.
I was speaking in terms of the v90CC which indeed is a 2.0L 16v I-4 however it produces 316hp 295tq and still gets 22/30 mpg compared to the E400’s 329 354 which to me is peanuts especially with the t6 having in my opinion** no turbo lag.