convert an existing hard copy of a drawing to Visio and ppt.

Hey there, I'm looking for an experienced freelancer to help me convert an existing hard copy of a "PROCESS FLOW DIAGRAM" to Visio and PowerPoint formats. this is a process flow diag showing how one process step is connected to several other process steps. This is NOT a graphical design, picture drawing or banner or anything complex. The hard copy drawing is about A3 size and I would need an exact replica of it in both Visio and PowerPoint files. Additionally, I do require some changes and enhancements to the existing drawing, so it must be done with care and attention to detail. Thanks in advance.