You can use the cleanup command in Maya to get rid of non-manifold vertices. Here are the steps:
1. Select the model you want to clean up.
2. Open the "Edit Mesh" menu and choose "Cleanup...".
3. In the "Cleanup Options" window, check the "Non-Manifold Geometry" option and click "OK".
4. Click the "Cleanup" button to remove the non-manifold vertices.
Following these steps will help you quickly get rid of non-manifold vertices in Maya.