Injectors are expensive. BUT, just like everything else, I searched for what I know to be reliable. Those little Mercedes mills can be found under the hood every 2012 (maybe newer) and older Mercedes, Dodge, and Freightliner sprinter van as well as liberties and Cherokees stateside and likely dozens more models overseas.
Working at the Dodge dealer years ago that was a Business+Link dealer, we got commercial vehicles in for service right and left. These sprinter things came in for oil changes and repairs by the dozen every week. Mainly oil changes. I don't think I ever saw a single new injector installed in that shop on those. Hundreds of transmissions, emissions systems issues....... And mileages ranging from 10k (first oil change) all the way up to 750k miles. I saw some rot apart before they needed any major work.
The preventative stuff is nothing compared to the problems they are intended to solve. And for low mileage engines, they aren't a huge concern, I just don't want to get caught with my pants down.
Reliability is key. And I try and do this type of preventative stuff to any vehicle I buy. Hell I have 10 grand probably into my truck that's only worth about 2,500 bucks.
I'm one who isn't afraid to spend a bit on a vehicle, to solve issues it is known to have. Every vehicle has common issues. If I can get to them before they become problems, I will. Bro straight up ran outta pockets is what he did.
Sent from my flagged XT1635-01
Tyler/T-Unit