Case study: Annual report
Recently, we worked with a corporate client who only needed us to proofread the second PDF of their annual report. They looked over the first one in-house and sent us the amended version. They then took ownership of the final proofs and finalised everything in-house.
This can be a good compromise if you want to ensure a good-quality output when you have a tight budget. It's always worth a professional proofreader having at least one look at some stage of the process (although we always prefer to see things through to completion, as you never know what errors can be introduced along the way).