MB-Sprinter for WoMo expand as needed?

I am looking for a Mercedes-Benz Sprinter L3H2 from year 2016 under 200’000km and under EUR 20’000. After a long search I have found two favourites with car dealers, but I am undecided what the better decision is (probe drives are agreed). Sprinter 1: 190’000km no paint damage/bulbs outside and no apparent rust at first sight, 1 passenger seat and year 2017. In the cargo room it has dents where the wheel is (don’t know how to say it), price of the 17’000 EUR. Unfortunately, this has no air conditioning, which I would have to retrofit, as we will also travel in warmer regions. Sprinter 2: 118’000km smaller bumps or dents and one/two show-finger-grosse Dellen, in which it has rust, double-beifharer seat and year 2016, price of the 20’000 EUR, 143hp. Now I have to go for the cheaper with more kilometers, with some rust lanes etc. It is important to replace some of the cars with a little seat.