You can’t outsource buy-in
One factor consistent with all of my most successful projects is that there is strong buy-in from staff. That is, the staff works very diligently to ensure the success of the project. They allocate the needed time, they learn what they need to know to be successful, and they execute on that.
The least successful projects are those where the organization feels they can "outsource" buy-in by having an external party serve as project manager and expect all of the work to be done by outside parties. As I like to point out to my clients, at some point, I get to leave and management of the system will be entirely on the organization. So staff needs to be working alongside the consultants so they know the system when the consultants leave.
You can't outsource buy-in. Staff needs to be invested from day one.