I've been asked for the reserve, should I provide it?

Since you have paid to have a hidden reserve it seems like a waste of money if you just let them know now. If you wanted the reserve to be known, you would have listed that way in the first place. You could answer along the lines of... Thanks for your question. Feel free to bid if you wish to and you might be lucky enough to win, but I am not willing to disclose the reserve at this time. 

WOW!  Excellent, thank you so much, I feel very green.

The usual answer in the old days used to be Q. What's the reserve?, A. It's the green bushy area down the road :)

I love it. A big thank you to everyone who took the time to help me out. What a great community.