Well I'm just back from DPA so here's the small details I can add. If you're having a reception AT 5pm then I don't think you have to pay the additional fee but if you're having a ceremony LATER than 5pm (say at 6pm like you wanted) then you might have the extra fee although I'm not sure why.
It sounds like you got a date now that you're happy with so that's awesome! As for picking a package, you don't really have to decide on that right away so you can wait and see how many people you end up booking and that might help work out your costs. We went with the most basic package (Wedding in Paradise I think?!) for which there was no cost and then paid for our reception meal separately. It was $25 per person, all plated (with GREAT service) and included a salad, soup, main course and dessert (separate from our cake) and all our guests seemed happy with the quantity. White and red house wine were served all through dinner, as well as any drinks that guests wanted to order. We had 33 people in total and didn't hear of anyone else going for buffet afterwards
Finally, I've got a couple different budget spreadsheets I think on my work computer but I won't have access to them for another day or so (yay for time off still!) but will try to get them posted soon!