If you're just going to the hotels to take a look around, it won't cost anything. When you get to the hotel guard post, tell them you want to check out the grounds. They'll write down your license tag number and wave you in. We visited five or six hotels that way, trying to decide where we'd like to honeymoon.
If you want to look at any of their ballrooms or specific event planning, you'll probably need someone to show you around though. Good luck!