Okay! I'll bite. After all I like you and you're kinda cute.
So, this lady with the key, what's got her knickers in a twist?
If they're not selling it, can someone make things for people with them paying for materials without being part of the merchant's guild?
What about if they are part of the merchant's guild?
I might think of other questions later, but that'll do for a start.
Appreciate the thought about being cute. Never had that one, so I'll have to think on that.
Lady with Key - she's apparently got it into her head to rip apart reality and make it fall apart. Not really sure as to why yet - crazy people have their own logic. I'm sure it makes perfect sense to her. Maybe separate the planes from ours to remove all magic from the world. Maybe she wants to tear it all down so she can rebuild it later. Maybe she just wants to kill herself but she's afraid to go alone. Not sure yet, never had a sit down with her. But she does have a definite plan and is ruthlessly perusing it. Just remember this: Almost no one sees themselves as the villain.
Yes, you can make things and sell them to Merchants. Very specifically in the Merchant Charter, it says they can buy things from Crafters AND members of the crafting guild at X2 their production value. Why you ask? It stops weird price changes. If, say Enslavement was a problem, a man might set his own price for antidotes that is crazy. But you can sell your wares directly to the Merchant's Guild without being a member.
Now membership in the Craftsman guild I'm sure has it's own benefits.
Now if you are a member of the Merchant's Guild, you have the right and ability to buy and sell items. You will not get a better price, since Merchants sell to Merchants at the same X2 production. But you could sell at market yourself. You are required to sell at minimum of X4 production cost to X6. After all, the Merchant has to make a profit.
This does not include things without a production value - So ritual casting / materials (Which usually falls under the perview of the Celestial Guild) you play negotiation games. Or if you want a Blacksmith to fix your armor - just negotiate the price.
Big thing people might encounter is Earth Guild members asking for compensation for healing. They spent a lot of time and effort into learning their craft and they got to feed themselves. Goods for a Service if you would.
Hope that answers your question. Ask more if you got them.