On other bags, he said, check the handles and underside for clues as to how often the bag might have been used.
But the most important consideration of all is a bag's rarity.
Given the demand now, Ji Tao, an auction expert said that auction prices are actually determining what prices some companies are charging for their new products in-store, in some cases increasing those considerably.
But arguably the most absurd development is that some handbags have become so valuable that they might never be used.
Rubinger said one of his clients hangs her precious "one-off" in a glass display case at home. It's never used, just watched.
Not surprisingly this modern doyen of the luxury market says China now has the potential of becoming the handbag capital of the world.
The strongest trend today is for cheerful, colorful bags, especially different shades of pink, he said.
And his advice to anyone thinking of buying one?
"Just like a desirable painting, you have to be in love with a bag first, and then decide how much you are willing to pay for it."