Hi
I just spent two months on bonaire(dutch cribbean) there is an iguana problem there too. The locals make iguana soup, legs, feets and all.woe to the unprepared tourist eating soup.
Even though i knew i would be there a short time i planted 5000 papaya seeds in pots,10-15 per pot, it would be a survival of the fittest event.
Neem tree seeds got mixed into some pots and those pots i set aside to be planted esewhere, i'm crazy about neems.
Iguana discovered my greenhouse and ate swaths of papaya seedlings,,,except the neems.
That got me to thinking that next time the seeds will only get water infused with neem leaf water.
Not neem seeds, just the leaf into a blender.
I also used blended neem leaf to pour over the sides of a basil plant pot to deter lizards. It seemed to work for that plant but i would need a larger test base to be really sure.
Ten years ago at the same nursery the lizards were eating the flowers off of several hundred potted plants.
I made a habanero spray that was so potent that i could not breath after i sprayed it right onto the morning flowers.
The lizards never noticed.
Just in case you start on a neem kick i also used neem leaf water to get the ticks off a friends dog and after a hot bonaire day i used neem water instead of soap or shampoo.
I smelled quite green.
It is a heartbreak that NE arizona is no good for neems.
Looking for neem? Check neem tree farm
online.