I second Tony. Build your habitat first of all. It should be as exciting and interesting as your frogs-- or nearly so. You will be creating a miniature rain forest, that will be more or less self sustaining and somewhat, (but not entirely) biologically balanced. The tanks don't require the rip-down-sterilizing, re-doing, etc. that habitats for other herps do. Learn about this as you read the care sheets for your frogs. Patrick Nabors at Saurian is definitely a great source or both frogs and help. There are other good sources, but I've only dealt with Patrick, so have no experience with others. Oh yes, be sure to start your fruit fly cultures well ahead of time.
While dart frogs are not high maintenance compared to a lot of other frogs and animals, neither can you ever neglect them. While it doesn't take hours, they do need daily attention.
I also agree with Tony about the starter frogs. Leukomelas are hardy, bold and fun. I think they'd be on top of my own list of starter frogs, although I didn't start with them myself.
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
3 D. galactonotus pumpkin orange splash back
5 D. imitator
4 D. leukomelas
4 D. pumilio Bastimentos
4 D. fantasticus pending