packaging storage relocation downsizing contingency planning decluttering collection policy
I'm fortunate I'm living in a pretty large flat with adequate built-in storage space, converted from a large late 19th/early 20th century house, but renting this privately on an renewable yearly tenancy agreement.
The most obvious candidates if I had to cull my fleet were those that weren't DCC ready and those with features not to my liking e.g. the plug and socket loco-tender arrangement on newer Hornby models. It took me ages to find the optimum solutions to store as many locos as possible, given I use a variety of boxes, including archive-style office supplies boxes (the best) and strong cardboard boxes e.g. those used for packaging electrical goods, not to mention the varying sizes of manufacturers' loco boxes. I've got things down to a fine art now so that only a few train packs (e.g. multiple units) aren't in those boxes.
I've found unless I substantially reduce my loco/MU fleet, I actually don't save a lot of space, however individual boxed locos don't get squashed up so much and storage boxes take less strain. The volume of packaging makes quite a difference and I think Lima and older style Bachmann boxes are still the best in terms of securely keeping the model intact and yet being compact in storage terms.
Yes, I could use self-storage solutions at a price, or store things at friends, but even though I'm still sorting out and bringing stuff back from my parents with the aim of keeping all my possessions together in one place, it's good discipline not to have too much clutter around.