I see what you are going for here...... Give people at the events an easy to remember domain, even if it is long. That is fine, but unfortunately it has no standalone value among domainers due to the very limited number of people who would want it. If you can find another photographer who can use it, it's hard to say what it's worth. $5? $50? Get what you can and don't let the first interested buyer walk away because there probably won't be a second one.