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One allowance here buys 24,790 EXP, the best of the 6 Lv 15 Carpenter tradecraft leves that record EXP: the runner-up manages 18,910 EXP, 24% less.

Across that rung the return runs from 7,170 EXP to 24,790 EXP per allowance — 5 distinct figures spanning 246%, so the wrong pick leaves 17,620 EXP of the allowance unspent.

On whether to wait: the best Lv 20 Carpenter tradecraft leve returns 28,010 EXP per allowance, 13% more than the best on this rung, while the Lv 10 rung behind tops out at 13,090 EXP.

At Lv 15 this data holds 52 leves paying EXP across 2 categories: the 48 Tradecraft ones average 16,554 EXP per allowance, the 4 Fieldcraft ones 78,432 EXP, which puts this leve 50% above its own category's average.

Gil ranks it differently: 240 gil per allowance is 2nd of 6 on the same rung against 1st on EXP, with the best there paying 350 gil.

Ash Mask (Lapis Lazuli) ×1 is a Lv 20 Carpenter recipe, 2 steps deep through 4 intermediates, costing 7 units of raw material and 6 crystals.

Handing that in returns 3,541 EXP and 34 gil for every unit of raw material the order swallows, and the tree needs Alchemist, Carpenter, Goldsmith and Leatherworker.