As an unpublished author, can I hire a ghostwriter to develop the book idea that I have?

Yes, you can do so successfully. As long as you are willing, prepared and able to put in the time and effort to collaborate openly and transparently. And pay the agreed fees when due. While the ghostwriter will assist you in getting an impactful and publishable manuscript out, the onus is on you to guide him promptly, as requested, to guarantee that the final manuscript epitomizes your “voice and tone.”

Good luck.