I had a few pieces pass through me that had various things etched into them - lot #'s, dealers initials, etc. It made me think that dubious dealers with a piece that had no hallmark could easily etch a common name and raise the price of the piece. Is there any way to keep them honest?
You never know what someone is capable of doing. The best defense is to become as knowledgeable as possible and use a place like this where you have a community that offers free feedback.