The ground school is 6-8 hours. Unless weather interferes, it's common to do it and then do one jump in the same day. No idea if they mind doing the ground school the week before - what matters is that you're 18 when you sign the waiver.
Don't know about Florida prices, but I would plan on at least 2, and more likely 3 to get the A license. 1500 sounds like the cost for the AFF portion only. To get the A, you need 4-5 coach jumps and 25 jumps total.
Combing the costs (and learning) of flying and skydiving may be challenging. May be best to focus on just one for a while.
I'll be done before I would start skydiving. I would like to get a rig but $$, I'm going to be a senior next year and then onto college to study something with avaition. After college i Would buy more. (if i like it skydiving of course.) Thanks