I was married at the Palladium in June so I will share with you what my costs were, as far as I know not much has changed since then, but again, I cannot be sure as costs with Mexico weddings change all the time. Your options for reception are:
1. Reserve space in one of the restaurants for your group, everyone will have to have the same dish, you will need to tell Rocio in advance what this dish is. You cannot have dancing or music here, and it will not be private, they will section off space for you. As far as I know, there is no additional cost for you to do this.
2. If you want a cocktail hour it is to take place immediately following your ceremony, the cost for this is 15-20$ per person, depending on if you do just beverage service or appetizers and beverages. This will take place where your ceremony took place, not after dinner.
3. If you want a private reception with a dance you have two options, neither one are on the beach, it will be Gran Azul or La Laguna, they are beautiful areas overlooking the pools, Laguna is on the Riveira side of the resort, Azul is on the Colonial/Kantenah. This will cost you a per plate fee depending on the menu choice, but I believe minimum is 45 or 50$ per person. If you want music you can bring an ipod and use their speakers, which alot of brides do, or you can hire a dj. You can have this reception from 7pm-11pm.
I think I answered all of the questions, I know Rocio takes quite a while to respond, and it is super annoying waiting for answers, but trust me once you get down there she has it all under control. Below is a link to my professional pictures from del Sol, you can see the ceremony and reception site and tons of other stuff. I got married in the Garden Gazebo and had my reception at La Laguna with a dj. ..:: Pictage | Registration ::..