I just discovered that with a high enough Handyman skill level, you can produce Guitars and Violins on the work bench. I haven't maxed this skill out yet so they might be able to produce more... we'll see.
But more than that, the instruments you produce have quality.
In general items manufactured or cultivated items come with varying degrees of quality ranging from poor, normal and excellent, and then there's the top of the scale:
For fruit / veggies, the ultimate is "Perfect."
For paintings the ultimate is "Masterpiece."
For writings / books, the ultimate is "Best-Seller."
I've been producing Excellent violins and guitars, and I'm wondering if there is something beyond that... like "Masterpiece" and whether it affects the sound of the music when played by the musician and whether that effects the tips when playing in public or the royalties on songs licensed.