Scope your CUI boundary before you buy a single tool
Every expensive CMMC program we have seen started the same way: buying an enclave, a SIEM, and a managed service before anyone wrote down which assets actually touch CUI.
Five categories, one decision each
CMMC scoping guidance splits your environment into CUI assets, security protection assets, contractor risk managed assets, specialized assets, and out-of-scope assets. Each asset gets exactly one category and a documented reason.
The categorization is the leverage point. Moving a class of workstations out of the CUI category — by removing CUI from them, not by relabeling — removes them from assessment scope entirely.
Write the reason, not just the label
An assessor will test the boundary by asking why a given asset is out of scope. 'It does not process, store, or transmit CUI, and here is the data-flow diagram that shows it' is an answer. A spreadsheet column that says out-of-scope is not.
Then, and only then, price the architecture
Once the inventory is categorized and the data flow is drawn, the architecture question becomes concrete: how few assets can legitimately hold CUI, and what does protecting exactly those cost? Teams that scope first routinely cut their in-scope asset count substantially before spending anything.