Ok sorry I can't tell you how much a sealer costs but they are worth it for sure!
It's like freezing it in time- you could get wet stuff and seal that and it won't mold, you just unseal and it will be more compact but otherwise right how you left it.
With all the ways your shit can be degraded or attacked I think vacuum seal is unrivaled as a long or medium term strategy.
*edit* Oh and as a last thought, the sealed bag is a layer of protection but you will want to keep it in a dark and cool climate too i'd imagine. No need to worry about what humidity stored in though.