Hi Tengu,
I've looked at and used storage on more than one occasion for various reasons.
Shipping container, bought or rented. Unless it's insulated your stuff will fry or freeze according to weather - if it's out of doors. If bought you need somewhere to store it (garden, friend's garden? But the truck delivering it has to be able to crane it in! They're a good price but may be more expensive for you than paying storage for however long you're away from your stuff.) Insulated ones have a decent resale value, or so I'm told.
Have you a friend with a warehouse, or office premises with some spare space that could keep your stuff?
My current landlord (while waiting for my house purchase to go through) has stuff stored in this loft with a big lock on it. May work for you? Leave anything particularly precious with family or friends?
Currently I'm living in rented with some stuff still boxed around me but most of my stuff is in a remover's storage unit a few miles away. You may find a local removal co. is not as expensive as the main guys. You may want periodic access to get stuff so make sure this is available if needed.
Have given up on lots of belongings after quite some time on the road. You can make do with less but you still need some stuff: photos, CDs, books, keepsakes. Have regretted some disposals so don't unless you're really sure.
Best wishes...