[joshvm]

Having been in this situation a few times as an adult, it's a mixture of stressful and cathartic figuring out exactly what's worth keeping, storing or giving away.

The best approach I've found is to standardize packing into 60L industrial Euro crates. They're inexpensive, very strong, practically waterproof (will survive both puddles and rain) and you can even air freight them at close to $100/box if the contents weigh under 32kg. Most of the expense in shipping is volume and people massively underestimate how much they own. If you can keep things compact and dense, ground/sea freight is inexpensive if you don't have to do it very often and there is no practical weight restriction.

Furniture only makes sense if you can re-claim 80+% of the void space in items like shelves, or if it completely flat packs, and if the cost of re-acquisition would be high. Shipping companies usually have minimum billable volume (say 2 cubic meters). I was able to send an apartment's worth of contents in the same volume that a couch would occupy.

For everything else, either buy quality used things that you can sell without much depreciation, or cheap used things that you don't mind thrifting afterwards.