I always ask a higher-than-market value if I'm putting an available for adoption notice out in the public's eye. It's a useful tool for screening qualified candidates for adopting the animal. Those who are too cheap to pay the fee will most likely be too cheap to take the animal to the vet or provide the best habitat.
I will sometimes lower or waive the fee if I know it's an animal that needs ongoing care and I have confidence that the adoptive owner will be providing that care with the help of a qualified reptile vet. Folks just have to prove they are capable of providing a good level of care. If an applicant has an available enclosure, good husbandry knowledge and uses a great vet but is low on funds to pay both my adoption fee and the vet bills I'm willing to cut them a break.
Fortunately most of my work is rehabbing post-operative animals who go back to their owners once they don't need stuff like stomach tubes or IVs anymore so I don't have to deal with that too very often. I really agonize over placing my animals in new homes. If I had to rehome all my charges I'd have bleeding ulcers and big bald patches where I've pulled out my hair.
The Zombie Mama is here!