The only reason I could think of for older roosters would be the amount of meat. Does he want older roosters or just any age? 20 is a lot either way.
He wants older ones.
Holy moly - I'm not sure what your setup is like, but with my limited experience with just a few roosters, I would think that that many year old roosters would take a lot of feed and a lot of housing (and, depending on the former, maybe a lot of rooster first aid). How do you do it?! (And what do you charge?!)
- Ant Farm