Although I am not a beginner as a collector, some posts in the last days have puzzled me. Like the grading in YYS4BOB's thread or motorman's remark that some models were "rare but not hard to find". I have always thought that "rare", "scarce" or "hard to find" were interchangeable - something that's not common. In German we just use the word "selten" for that (and everything is "selten" on ebay anyway), so I was a bit surprised to see such distinctions made between "rare", "scarce", "HTF". YYS4BOB even mentioned "difficult" which I haven't seen before and don't know where this would fit in the "Scarcity Intensity Scale".
So, please can anybody shed some light - which is the correct order of scarcity, starting with "common" and going into "holy grail" territory - and what would be the typical availability of a "rare" or "scarce" item? Like, is a version seen once or twice per year "rare", "scarce", "HTF" or "VHTF"?
