Depends on a ton of things:
How much revenue you've got running through your business.
Any complicated tax or accounting transactions associated with it
Type of business
Are you providing financials
Past accuracy of the financials you've provided
Does the CPA do an annual compilation and review of your books or an audit
What the CPA feels their risk assessment is in taking you on as a client.
Big firm, small firm, individual CPA performing the tax work

It honestly could be anywhere between $500 and $15,000 depending on the scope of the engagement.