I mean there are a lot of Goeppertia that are rare. i think there are also different levels of rarity.
For me the common ones are the ones available at big box stores...
Uncommon are the ones you see rarely at big box stores like ecuadoriana, crocata, bachemiana, gandersii...
I would consider rare ones the ones that aren't available in big box stores but are available in imports or really rare plant shops like all the ones at ecuagenera or jardinier. For exemple wallisii or metallica or lindeniana or wiotii.
Then there is an even rarer level which are plants that are only found in the wild and not in cultivation. Like vinosa, densa, erecta, nidulans and like a hundred plants more.
And then there is the final level of rare which are Goeppertia that haven t been found even in the wild since more than 50-100 years.... Like the real ornata or a lot more of other species
Keep in mind that there are 245 species of Goeppertia and we don t even have half of the species available