Hi,can anyone help with advice regarding the cheapest way to experience Discovery Cove/swim with dolphins in August for 2 Adults/2 children(13 and7)..is it better to buy here or wait and see if there are any offers on when we arrive in Orlando?Also can you reserve tickets for the Dolphin swim here in the UK and pay on arrival in the US?any help would be great..it would be the end of August beginning of September...