Depends a bit.  When you say Master Clients with sub-projects. Are the sub-projects on the client level using a Client.Project naming system? Or are you using References to subtotal one big bill by the sub-projects?

Client level records can be added viaCSV file with TSImport, but the references I would probably say should be done as a template reference (assuming the same reference for all) that is then just shared amongst all the the Master Clients.

Nancy Duhon, Esq.
Duhon Technology Solutions, LLC
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