STL Model Reshape for Printing

I have an existing 3D model in STL format that needs several changes before it will be ready for the printer. The piece must be resized to exact specifications, certain features have to be added or removed,... (Budget: ₹600 - ₹1500 INR, Jobs: 3D Animation, 3D CAD, 3D Design, 3D Modelling, 3D Printing, 3D Rendering, Blender, Solidworks)