Hello. I am needing to know what version of Final Cut pro can I use that will handle the clips from a Canon t5i and a Canon XF205...does anyone know?

The latest version can, FCP-X. FCP 7.0.3 could work with the Canon XF camera, but ONLY if you already have the XF Log and transfer plugin. Without that, you need external tools (EditReady) to convert the footage to ProRes. The T5i doesn't have a log and transfer workflow with FCP 7...so it too would need to be converted outside of FCP...with Compressor or EditReady as well.

Both need to be converted to ProRes before bringing into FCP 7. FCP 6 should work as well, as long as it's converted before hand. But only FCX will directly access this footage and work with it...and convert it to ProRes 422, or to Proxy if you need to conserve space.