VPD vs multiple schems vs multiple instance

Hi all,

We are developing an application that uses Oracle database. We may be hosting this application for multiple clients (expecting 2-4 deployments). The application and the database will remain exactly same for each clients. I have the following options for the database, each has its own advantages and disadvantages to me at the first sight.

1. Create different schemas for different clients.
2. Create different instances for each clients.
3. Create VPD aka RLS in one single instance and single schema.

Expected database size over 2 years for each client will be 400 GB, with largest table size reaching up to 40 to 60 million rows. We will be using xmltype in 3-4 tables.

Has anyone gone through such scenario and can tell their reason for selecting their option?

Any input is highly appreciated.

Thanks

Sandeep

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