When the skill level is at its maximum, fee of personal shop decreases by ([skill level] - [max. level]) * 1%.
Repair max lv 15
(15-15) x 1%
=0 x 1%
The description is bogus. You have to pay a tax on your revenue on all shops, and this gem probably reduces the tax by 1%.
Since the tax is 10% if my memory doesn’t betray me, using a skill gem would reduce the tax to 9%.
Also, the math you used is wrong:
it’s obviously 0% without the skill gem.
with the repair gem equipped, you get:
( - ) * 1% = 1% shop fee reduction
Pretty sure tax is 30%, at least thats what it used to be.
skill lv 16? ah, with gem, of course! Forgot gem make it lv 16.
-1% for 50m repair gem at market, not worth at all.
Depends on your shop. If you have hotspot shop with like monthly 150m+ monthly sales, that’s a pretty reasonable profit increase without even doing anything. That lv16 on your sign alone adds huge promotional value to your shop.