I've definitely tried to with NC items, and as much as egaeus gets on my nerves, he's not wrong about the DTI stats (specifically the # of ppl who have the item UFT) being a decent indicator of what has the potential to inflate in the future xD
Other factors to consider are whether an item is currently being re-released/RR'ed (probably won't go up in value anymore) or has RR'ed in the past (an indication that it may RR again in the future), so generally old items that have never RR'ed are a good bet. And like Flordibel said, it's important also to consider aesthetic! Purple/pink, pastel, floral themes, space themes, and fantasy themes are all well-loved
That said, it generally takes months or years for the items to actually go up drastically in value
I've sat on nice-looking HTF ~1-2 cap items for years before they finally went up to like 6+ caps