Graco magnum pro x9 tear down & rebuild

Do you only repair phones and the like or can you fix other things as well? If so I have a Graco Magnun Pro x9 airless paint sprayer that was used on a job but was never cleaned afterwards. That was years ago so it is now rusted due to exposure to the elements and all the paint is hard dried. I know it’s best to buy a new one but I can’t afford it so I’m working with wat I have can you help me