It’s not just meditation, but it’s also a strict diet. https://en.wikipedia.org/wiki/Buddhist_mummy

Money can be exchanged for goods and services.

Twenty dollars can buy many peanuts.

Depends on which world you end up on… because there are quite a few Space Marine legions you don’t want to be invaded by.

Not to mention that the nuclear fuel can be recycled, albeit with some loss, but (at least in the USA) you’re legally not allowed to do that.