When Microwaves first came out they were huge but with a tiny cooking area and they were not affordable, and were mostly in business kitchens and a few restaurants. I would love a freeze dryer but the cheapest I have seen is $1600 and they only have 4 small trays.
Sometimes you can find filterable/purificiable water when you’re in nature. If you can’t you should reconsider where your planning to go.