There is a big misunderstanding about the role of ERP and CRM vendors. The common assumption is that ERP and CRM vendors are responsible for implementing their products based on your specific needs. If you assume that the vendors will offer a turnkey solution by default, you are making a big mistake!
The fact is that the vendors play a relatively much smaller role in the project. The customer-side Project team is typically responsible for most of the work. The vendors are responsible for configuring/customising the software based on your needs. However, generally, the customer-side project team is accountable for providing requirements, test execution, data migration, training, change management, user security, workflows, and Project management.
In the whole schema of things, the vendors play a relatively minor role in the implementation. Unless agreed otherwise, typically, your team will do most of the work.
Are you ready for it?