I am keenly aware that I cannot compete with exH's holidays. In the past he has taken our DCs to luxury resorts in Majorca and Portugal. They always have the "best time ever" with him. This year he is taking them to Florida for 2 weeks. 
For the past 3 years I have gone self catering with DCs and my parents. It has been a nice break for me as DM does most of the cooking and DF does most of the driving, but it has been a bit boring for my DCs as we go to places in the middle of nowhere with no other kids to play with and very little entertainment.
So this year I want to take them on my own to a resort somewhere hot, all inclusive with kids club, pools and entertainment in the last week of August. What can I expect to pay for that? And where should I look?