To be honest, Binder, it's gonna be an RP thing either way for the most part most likely.
Is he a guy who wants to sell his own craft, and who buys stock and material? Appraise makes sense.
Is he a guy who's more interested in intricate detail work, and the fine mechanics of springs and clockwork? Disable Device has you covered.
Either will be useful in its own baliwick. Neither's likely to be all -that- useful to him anytime soon.
Is he a guy who wants to sell his own craft, and who buys stock and material? Appraise makes sense.
Is he a guy who's more interested in intricate detail work, and the fine mechanics of springs and clockwork? Disable Device has you covered.
Either will be useful in its own baliwick. Neither's likely to be all -that- useful to him anytime soon.