>>55039665but anyways.
That's why you should not be an investor-brain. Pokemon nowadays is nota lipper-friendly field.
It's basically just a bunch of confused weiros that buying random stuff in HOPES of "doing big profit 10 years later".
Just collect what you want. Complete a master set because it means something to you.
+ if it has rarest promos it will be sort of an investiment too. Because rare promos will be nearly unabtainable 10+ years later.
And if you wont be selling them separated from your master set - it will be sold.
We live in a modern era - everything is a speculation because we are not even 5 years old yet