Here is rule number one of art buying: if you can just walk up cold and buy it, don’t.
For mysterious reasons unbeknownst to this cultural economist, the best artworks are rationed out to regular and longstanding buyers. (Is it somehow price discrimination — make people work very hard to get the best — or does a gallery care about the quality/reputation of its buyers? Or does it support market value to have excess yet rationed demand at the going price, a bit like a long line at a restaurant to signal popularity? And what determines whether a work is sold through a gallery or at auction?)
Here is my earlier post on Picasso and Costco.