I would say that if you built it out of wood palettes, you should be able to rebuild it easily & cheaply enough when the time comes. Plus it will give you the opportunity to fix anything you think could be improved.
One of my biggest mistakes was trying to build something (my "forever home") that would last my lifetime when I should have built something that was good enough for the time.
Creator of Shire Silver, a precious metals based currency. I work on a permaculture farm. Old nerd. Father.