HubSpot supports restricting pages and blog posts to registered members, subject to your subscription. Native private-content settings for these require Content Hub Professional or Enterprise.
Your traditional email approach is completely valid: collect subscribers, organise the list and send a professionally designed HTML newsletter containing the full insights each week. Readers wouldn’t need to log in, and you wouldn’t need to build a gated content section to launch.
The trade-off is straightforward:
For Vault: if you mean your real estate CRM, managing the subscriber list and EDMs there depends on its email features and your account. I wouldn’t assume it automatically syncs VIPSCLUB membership, tiers or unsubscribes with HubSpot. Choose one system to manage newsletter subscriptions and sending, or explicitly set up that sync.
My suggestion for this campaign: start with the public landing page and full-content email newsletters. Add a VIPSCLUB blog archive when you have a regular publishing routine. A gated archive is useful, but it isn’t a prerequisite for delivering the promised insights.