Hey Gnorman buddy, just reading through your nice little rogue generic class, and saw this tidbit:
Moderate Archetype Power: An artificer reduces any requirements for crafting (be it time, experience points, or gold pieces), by a percentage equal to five times his Intelligence modifier (provided that it is positive). This ability stacks with similar feats. In addition, any splash weapons thrown by an artificer have their radius and damage doubled.
Now, I'm curious about the way you worded that. When you say stack with other feats, do you mean that it would (A) directly improve a percentage, or that it would (B) follow standard item creation multiplicative guidelines? For example:
There is an artificer with the Extraordinary Artisan feat (which reduces costs in GP by 25%). He has an intelligence modifier of +5. He wishes to craft an item, so his cost in GP would be either:
(A) 100% - 25% - 25% = 50% of the standard cost.
(B) 100% * 75% * 75% = 56.25% of the standard cost.