Hi zerotoone,
One of the 'keys' to improving your GMAT Score is to define how efficiently you are approaching the overall Exam. The types of improvements that lead to higher Scores can be based on a variety of different things - including your content knowledge, your use of Tactics and how you organize your work (your note-taking, labeling, etc.). A tutor could potentially help you improve in those areas, but that does not mean that a tutor is the only way to make those improvements.
I've actually just sent you a PM with an analysis of your Enhanced Score Report - with some suggestions on how you can make those improvements without hiring a tutor.
GMAT assassins aren't born, they're made,
Rich