Some of those posting know about collectibles (and I know nothing).

My ha'porth is that what isn't fashionable and highly desirable now might be in future, but you don't know how long that'd take. I learned this on clearing relatives' houses.

Not everyone who'd look at your items is a long-term collector. I know a few collecting friends & acquaintances who every few years change (or have to change) what they collect, with the attic crammed with past collections (we've all done it?).

I can also see why someone'd be tempted by your items individually as they're appealing. (That's how many collectors start?) And not everyone scours charity shops or car boot sales: as I get older and more crotchety the more I prefer the comfort of online shopping.