There are two aspects to pricing. The margin you make at different price levels vs the likely impact on demand. The second of these is the tricky thing to model. If you have historic data where you have tried different pricing levels then you might have the information you need to model something based on that. You can also use market research amongst customers and prospects to test pricing so that you can get the latter part of the equation (that is likely overkill for a small business but worth considering for a larger business).
The end result might be trickier to model for a service business (as often the concept of "an average contract" is a problematic one - i.e. there is no such thing as an average contract).
If you are a smaller business and time and budgets are likely to be limited then you are realistically limited to using Excel. Essentially you will need a total price the customer pays, the margin you make at that price level and a factor/estimate for the likely impact on demand at that price level (which may come from your own historic data or market research or ... dare I say - guessing). Needless to say if the estimated demand factor input is 100% guessing it is likely to be a waste of time doing it.
If you are looking to do anything more sophisticated than that, then you are probably in the realms of spending a few grand. SPSS (stats software) has a pricing modeller but the price of that is in the "phone up a consultant to discuss it" territory (i.e. thousands of pounds). Larger businesses that go in for that would probably take on a consultant economist or accountant to do it, or have someone senior from their own accounts team spend a few days on it.
If you'd like to find out more about the market research side I'd be happy to share more so feel free to ask, or message me.
