Wow.
My brother has a 2018 MB Sprinter. None of these issues.
You guys are making some of this up. Right?
They just used a crappy mechanic. The rust is factual though, but smart people who lurk on sprinter source drill some drain holes to let the water out of the quarter panels and that helps with the rust.
The transmission is used in lots of dodge and Chryslers and shouldn't be 13,000 to fix or replace, so he got scammed there too.
I've helped my dad with his 2007 sprinter since he bought it. We've done injectors, all the intercooler piping and gaskets, the intercooler, oil cooler seals, turbo exhaust gaskets, turbo oil gaskets, turbo pedestal gaskets, transgo valve body kit, new dpf, transmission filter, deleted the two espar heaters and the rear heater core, new coolant hoses, new coolant bottle, deleted the swirl flaps and cleaned the intake (at the same time as the oil cooler) new starter, new rear leaf springs, rebuilt front suspension, new brakes, new parking brakes, new tires, new headlights, fixed ghetto rear a/c. And the windshield rusted out so we welded new metal around the windshield.
It still needs to rust on the frame patched. It was a shuttle bus in Canada for the first 60,000 miles of it's life. He bought it for $11,000 and put $10,000 into repairs since then. It had 60k miles when we bought it and it now has 130,000 miles.
Find another sprinter van with no issues and 60,000 miles for $20k. (He did all the repairs except the rear springs and the coolant bottle when we first bought it.