Our project is pursuing Enhanced Cx credit v2009. Our company as Design & Construction General Contractor has professionals in house with Commissioning experience capable of coordinating the full Cx Process. 

Can we Coordinate and implement our own Commissioning and only have the owner's CxA consultant come in only to review (design phase) and witness (construction phase) to approve the Commissioning process as a third party?  (any changes he requests will be attended)

Or will the CxA's company have to coordinate and implement the Cx Process for it to be valid as a third party?

Is there any difference though? It is my understanding that the CxA will specify Cx requirements for design team to include in drawings + design documents. And CxA will witness TAB, FPT, and other requirements during construction for Subcontractors to perform onsite and include. 

So either way our team will implement the Cx, and CxA will oversee as third party and make sure we comply. 

anyone with Commissioning experience might identify my inquiry...

Thank you,