Hi John,
I have never tested this but I guess you can do the following:
1: During SDDC bringup, only provide details of 4 Esxi hosts in the deployment parameter sheet and let the mgmt cluster stood up with vSAN storage.
2: Add new cluster with remaining 9 Esxi hosts and use NFS endpoint IP to map the exported shares as datastore on the remaining Esxi hosts.
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Manish Jha | Operations Support Engineer | vCloud Air Operations
vExpert 2015-17 | vExpert-NSX | vExpert-Cloud | VCAP6-DCV | VCP6-DCV | RHCE-7
Website : http://vstellar.com