In my experience I find that tree frogs are a great first frog to have, they don't mind being handled and enjoy being perched on your arm. A grey tree frog is probably the cheapest option just because they can be found all across NA. White's tree frogs are very easy to take care of and I'd absolutely recommend them because they are large. By the way toads often despise being handled even though they are rougher species so suitable for handling. And a species of chorus frog that you can buy are Spring Peepers, but all chorus frogs are very small so cannot be handled much, and food is always hard to find.