I'd heed the last advice. I decided to jump in feet first and bought a sixteen foot rod
A long rod is not just about gaining extra distance in the cast, there are other as important benefits.
For example, if there is a lot of weed in your swim, having a long rod will help to keep your line above the weed at the waters edge, its also handy if you are fishing a surf beach because you can get the rod/line above most of the surf, which in turn will aid bite detection.
Also handy for when you are using long traces,.....have you tried casting a 14ft trace with a 12ft rod
So I guess some of your decision needs to be based on what type of venues you will be fishing, and taget species.
I started my seafishing last year with a cheap fixed spool reel and 12ft beach caster, and it served me well for the first 3/4 months, but as my knowledge of the sport grew, so indeed did the amount of tackle I bought. I also realised that I enjoyed the sport and would stick at it, and not banish the gear I splashed out on to the garden shed never to be seen or used again.
I soon improved the quality of my rods and reels, and now have gear which will suit many different fishing environments. I still have the cheapo set I started with, and its great to let the odd none fishing friend use this when they come out with me. I'm not fearful then that they will damage my more expensive gear.