HELP!!!

I am in the very very beginning stages of trying to plan a destination wedding. My fiance and I want to have our destination wedding on Renaissance Island through Renaissance Aruba Resort and Casino. Does anyone have any tips or guidance on how to first approach planning this? My fiance really wants to get an idea of pricing before we dive in commit, but at this point, we have no idea if we'll have 10 or 50 guests.

Should we get married legally in the US first?

Wedding party? Is it a lot to ask people to come to your wedding that is being held out of the country and then ask people to commit to being IN the wedding?

Has anyone dealt with Renaissance Aruba? Are their vendors for flowers, photography, DJ, makeup, etc., worth it?

What are the pros/cons of working with a travel agent? Do you really need one? Should I try to block off rooms for my guests or give them all of the information to make their own travel arrangements?

Any tips or advice on how to begin with this would be great!

Laura