>Neither of those is likely to happen on the first trips to Mars.

It doesn't have to happen on the first trip. They could send the truck to Mars on one of the current rockets and just have it sit there until they're ready to use it. It's an electric vehicle. There's plenty of solar exposure on Mars, they can charge it over the course of weeks if they needed to, even though they don't, and the durability would guarantee that it could serve up there for years. It could literally just sit there and do nothing for the 3-5 years it takes them to build out a basic hab and a dock for it.