Modify an existing PCB Schematic/layout

My project is to modify an existing PCB schematic/layout. I need to add new features, and I already have the existing schematic and layout on hand. I also have some restrictions on the components that I will be using for this project. I'm looking for an experienced PCB designer who is up with the latest technology and has a good understanding of manufacturing guidelines. The designer should be familiar with various CAD packages, such as Altium or Eagle, and should be able to help ensure that my design is optimized for production. The project will involve modifying the existing schematic and layout for my PCB, as well as creating any necessary symbols, packages, or footprints that may be required. This project should be completed in a timely manner, and the end result should accurately reflect my desired changes.