Then charge them and see how the market reacts.
Or start another thread seeking an echo chamber for your inane chatter.
What do you want, an "IBB stamp of approval" to show your customers your billing is justified?
The market sets the pricing in the long run. If you add $50-$100 to every job while other shops don't, you could become "that shifty shop that always tacks on an extra charge" and you lose customers. If your shop rate is $110 & the shop down the block's is $135 but they don't have that "sleazy" reputation, they may be charging
more per job than you; while they have customers lined up to take a fucking, customers thankful to have an alternative to "Upcharge Jimmy".
People are generally reasonable - it just takes
clear communication so they don't think you're hosing them.
If you want more than the shop across town for the same job, you need to communicate the additional value.
Based on this thread & same thread(s) on PBB, the communication is where you're going to fuck yourself