If you're not sure that you really want to join the dark side, then renting a decent well set up instrument is a good way to find out. It's important that it be a good instrument so that it's not impeding your progress and your fun. Consider a DB teacher to be essential to develop good technique and habits and to avoid injury.
If you do become serious about the DB, I'm a believer in getting the very best instrument that you can (within reason).
Famous last words: And with that- Im gone. You will probably read in the paper soon about a deranged kid who burns his bass in front of a luthier.