The CxA’s prior project experience should be similar to the project for which the CxA is being hired. Project size is one aspect to consider, but certainly not the most important or only consideration. The experience should include projects with similar (or more complex) system types or space types. For example, if your project involves the construction of a hospital with complex systems serving multiple critical zones with a vast array of controls, it would be most beneficial to employ a CxA with documented experience commissioning a project with similar characteristics. But a CxA with extensive experience in commercial office space which has central systems and ventilation systems would most likely be able to handle a school.