The Batcave only has 3 levels. The first floor has the Batcomputer, the Batmobile, and a large pond that leads outside with the Batboat sitting in it. You can either fly, grapple up, or use the elevator to get to the second floor. The second floor has several breakable packages and an interactiable bookcase. Interacting with it will cause it to moves out tf the way, leaving an entrance to Wayne Manor. The second floor also has a staircase, which leads to the third and last floor. It has the Batwing, Batcycle, a few small computers, a T-rex, and a giant Penny.
The Batmobile, Batboat, Batwing, and Batcycle are all able to be bought for 50,000 bits. The Batcomputer can access info and bios on all characters and how much they cost. The every and each breakable package on the second floor (7) contain 5 bits, equaling 50,035 bits in all.