Converting Shed to Office - GC or Handyman?

We have an existing 200 sqft shed that we want to convert to an office. It already has electric, but needs the basics (insulation, drywall, etc.) and some more complex fixes (reframing and install of door & window, siding repairs, confirmation of foundation). Is it best to hire a GC or a handyman for this?

I think we could do a lot of the basics ourselves, but the complex fixes are definitely out of our depth.