IMO the single most important factor when buying a Leopard wrasse, or any sand-burying wrasse for that matter, is to very closely inspect the mouth/jaw of the fish. Because it is impossible to ship fish with sand, or for most wholesalers/distributors to keep tanks with sand for these guys, they are often relentless in their attempt to bury themselves in tanks without sand. This more often then not results in them damaging their mouths. For any high-metabolism/pod-eater, this is death sentence when they can't eat.
As mentioned above, a 65gal should be large enough for a leopard wrasse, pending there isn't competition for food.