I haven't tried selling anything on ebay, but IMO descriptive words such as "rare", "art deco"

or even "original" are tired, overused & too subjective to belong in the auction heading. I like the Jack Webb approach--"Just the facts, ma'am". If a description is desired or needed, I'd save it for the paragraph that accompanies the picture. And, instead of rare, terms like "uncommon" or "few listed" seem more accurate to me.