You can get away with 3 floors inside. I sued 3 wide foundation from front to back. The front allows 2-levels while the back near the entrance is only tall enough for 2 floors. If you are like me and love platform bases. This one's one of the best. Awesome views, decent space and building the foundations was incredibly easy. It's seems to board players and tames to specific areas so id avoid this feature if you intend to build a base. Or don't build a large interior if you intend to store dinos. Which while I'm talking about it. Tames glitch out when the sub clips into the terrain, so best to leave tames in their cryos or simply leave them home🙂