Can you help me update my existing website that another web firm built?

Yes and No.

We only support websites that are built using WordPress.

As per our experience Finishing Half build website takes more time to complete then from Scratch. We advise all our clients to let us redo complete website from scratch.

We have this policy so that we can 100% stand behind everything that we craft. There are issues of liability of multiple programmers touching the same code over time.