On LawTrades, our data shows employment contracts being reviewed for fixed-rates of $400-$900 depending on the complexity.
The ambiguity of the employment relationship will likely dictate the price you will pay. However, be wary of overpaying at a law firm. Finding a formidable lawyer to help you draft an affordable employment contract efficiently isn't always easy. Don't expect to find a good lawyer by just doing a Google search or reading an advertisement (unless you have ample time to spend). There is simply not enough information in those outlets to help you make an valid judgement.
To help alleviate this pain point, we started LawTrades because we know how hard it can be to find the right lawyer, let alone someone who is available and within your budget.