I have Grey Tree Frogs so Im not too familiar with the ones you are thinking about.
For Starters I love how you are listening to many of the threads and not mixing species... next I would wait till all the care articles for the frogs are back up and running and read the care sheet on those you are interested. Make sure you can suppy the proper food, habitat, temp, lighting and humidity and any other specifics those frogs might need. It might help narrow it down a bit =). Also for 3 frogs I hope you have atleast a 30 gallon terrarium and tree frogs prefer height so a min of 24inches high is ideal. Rule of thumb you will read alot here is min 10 gallons per Frog. Hope this helped a lil!