Thank you, Adam.  Your thoughts and experience are helpful...the addition of  thumbs to an order sheet is excellent.

Yes, I will be the only exhibitor.  In fact,  I work just a few steps away from the exhibit.  This is perhaps a good thing since anyone who might mention the "photographer" at the exhibit will likely be told he is actually near by.   Orders can be collected at the exhibit or even brought to me directly.  

Again, I am assuming the big IF that someone actually wants to purchase a photo...I do believe a few will sell but that is not truly my reason for the participation.  For me, this is quite personal and almost like standing naked on a steet corner at high noon.  I assume one can learn to be calm once that has happened more than once...