Since they are frequently in contact with dealers, they usually know where to get good buys. Be sure to get tangible results. The natural outcome of the consulting process is a recommendation. A description of the current situation and the technical or business reasons for choosing a course of action are key parts as well. Be sure this is all captured in written form at regular intervals.
Most consultants provide a report.
Insist on a high-quality written report. Summary Select a general computer consultant first, use other computer professionals for specific tasks. Ask about charges early. There is a lot of variation, so don't make assumptions. Be sure you can see how the proposed solution fits into your business.