Hi,
I too took the kaplan course. You will only maximize the $999 class if you come to class prepared and if you go to the learning library and work the practice sets they have there. I also had the barron's book, but if you read previous posts, you'll see that the book has some errors in it.
I studied seriously for about a month, probably about 2-3 hrs each day. I kicked it into overdrive about 2 weeks before I took the DAT, probably studying about 2-3 hrs diligently, another 1-2 hrs not-so-diligently. The last 3 or 4 days before you take it, I would recommend no or only light studying (I tried to cram like mad, but I think it just freaked me out even more). Best advice would be to go to bed early and try to get good sleep before you take it!
good luck! 🙂