Some agencies keep the keys. Login credentials sit with them, the CMS is a proprietary black box, and leaving means starting over somewhere else. That is not how Core Techno structures a project. Once a site is live, the domain, hosting arrangement and CMS access belong to the client, documented clearly enough that another developer could pick up the work if they ever needed to.
That said, ownership works differently depending on the build. A WordPress site hands over cleanly because the platform itself is standard. A fully custom application takes more handover documentation, and Core Techno is upfront about that difference before the project starts, not after it ends.