When wondering why someone charges so much for a repair, consider the hours potentially involved, and then call a local mechanic shop (or even some place like “Jiffy Lube”) and ask what their price is per shop-time hour.
(Usually the answer will be in the neighborhood of $120/hr. Or more…)
Then do the math: ten hours is $1,200… two days’ work (16 hrs) is $1,920…just for labor. If parts are involved, it’s more.
If you think the skill level of a double bass luthier is so much less than that of a VW mechanic, or whatever (a plumber???) then that will affect your thinking too.
In a one man shop, it looks as though the “mechanic” is getting all the money. But the general overhead takes the lion’s share. All things to remember.
Ah, well. Everyone here knows I advocate working on one’s own bass… but I also know where to draw a line and hire someone.
And… when I came here, many years ago, I was respectful to those who offered the advice I requested.
Your call. Good luck with your project.