Hmmm tough question
I would first purchase a piece of large land and make sure there is a huge pool of water in there for the pair of salt water crocs I would get. I would add some trees fora pair of biak green tree pythons . Now a pair of gila monsters would be cool. and how about we finish off the herp list with a pair of aussie water dragons and a pair of crocodile lizards.
I would then make a nice rock area in the enclosure with a small pond just for the croc lizards. A free flowing river of mice and rats. And for the crocs a flowing river of zebras.Of course crickets for the other lizards. Hmmm some nice plants around the enclosure sure would spiffy things up.It's also an outdoor enclosure.
I think thats it...maybe a koi pond in there too wih working water fall.