I completely understand your desire to include an adoption fee to "weed out" interested individuals who aren't fully committed or aware of what they are getting into. I also understand how difficult it can be to place an iguana this size. I'm not sure of whether you're aware of this or not, but if you go to the Green Iguana Society's webpage (
http://www.greenigsociety.org/) they have a great adoption board. The nice thing about their adoption board is that you have the option of allowing green iguana society administrators to screen all potential adoption applications for you. This is a nice tool to make sure of who you're adopting to. Such a beautiful blue iguana that is so healthy would definately attract attention, particularly if you had some nice photos. Forgive me if this is an option you've already tried. I just wanted to throw it out there as a suggestion for you to try as opposed to putting him down. Good Luck!