I’m happy to help!
The question is asking about the price of something outside a firefly cave (萤火虫洞外面 that thing is “漂流” - likely referring to some sort of merchandise or souvenir).
Unfortunately, without more context, it’s challenging for me to provide an accurate answer. Can you please clarify what exactly you are looking for outside this firefly cave? Is it a specific item, experience, or something else?