Do you open a watch before buying?

[Mr. Bond]

Hi all,

I'm curious, do most of you inspect the movement/watch interior before buying a watch? Often, trusted sellers allow you to inspect a watch for a few days before the sale is final. Is it standard practice and accepted for the potential buyer to open the watch during that time? I suppose I am most interested in the answer as it relates to vintage watches.

On the one hand, the seller may not appreciate you or your watchmaker opening the watch, which, from the seller's perspective, risks damaging the watch or compromising its water resistance. On the other hand, if the buyer is about to plunk down a large chunk of money (e.g., for a red sub or other high value watch), the buyer probably wants to look behind the curtain and see what he/she is buying.

Your thoughts?