One of my worldbuilding "things" is to toss in very specific, concrete details that have to immediate relevance to the overall story in the moment, but will then be available as settings or resources in the future.
In Daughter of Mystery, when Margerit's relatives come to visit her in Rotenek at the Advent season, I had a passing mention of her taking her cousins to the "Strangers' Market" as a sort o tourist attraction. With a couple other passing references, I began to establish that this was a not-entirely-authorized institution on the edges of the wharf district (later established that it's in the vicinity of the Nikuleplaiz) where men who work on ships make a little on the side selling "exotic" trinkets that they've picked up in their travels, or perhaps handcrafts they make in idle hours on shipboard. (When I say "ships", we're talking about river barges and the like by the time they get to Rotenek, but I envision the workforce to have a lot of carryover from wider travel.)
So when Aukustin wants a taste of the wider world in The Mystic Marriage, he gets Tio to take him on an excursion to the Strangers' Market, with entirely too adventurous results. When Serafina wants to replace the broken bottle of hair oil that came originally from Alexandria, Luzie suggests the Strangers' Market as a good place to look. And that is where Serafina spots a very special little icon to give as a present.
The following scene wasn't in the original draft of Mother of Souls; I added it in revisions. The delivery of the gift had already been there, but I wanted to set it up a bit more. To give Serafina a chance to think about gifts both received and given. (And given that I needed her to be functionally destitute shortly afterward, there was a certain pearl necklace that I needed to dispose of.)
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Chapter 30 - Serafina
Summer shifted the wares in the Strangers’ Market from the bright luxuries meant to tempt shoppers from the upper town to still rare but more practical goods offered to those unmoved by the seasons. One last errand brought Serafina’s steps to a booth presided over by a white-haired and wizened man. He sat behind the counter clutching one of the strings of beads that made the bulk of his wares, slipping the counters through his fingers and muttering over them one by one. She hadn’t come to view the rosaries, but she examined several of the more precious ones to distract from the object of her true interest. Coral and crystal, lapis and silver gilt. She hesitated, and reached for a more humble string of enameled beads whose pendant cross was made from a piece of rolled tin.
The man paused in his counting. “Not the one for a fine lady like you.”
Serafina ignored the empty flattery. She was returning to Rome in the same worn blue pelisse she had arrived in. No one would mistake her for a fine lady. She had one thing of value remaining and it sat hidden in the reticule dangling from her wrist.
“No,” she echoed. “That one’s not for a fine lady. The cross holds a relic, save it for someone who needs help.” It was a guess, but a faint glow of power leaked from the seams of the metal.
Now she turned her attention to her goal: a collection of small figures standing at one end of the counter. There was no time for long bargaining. She slid her choice to the center of the space.
“An excellent choice. Very fine workmanship. Said to be—”
“Do you take trade?” she interrupted.
His eyes narrowed.
Serafina loosened the strings on her reticule and pulled out the pearl necklace. She hadn’t worn it since the Royal Guild dinner…it seemed so long ago. She thought of Marianniz. If it had been a gift of the heart, she wouldn’t think of parting with it, but…
“An even trade. I think you will have the bargain of it.”
The man fingered the pearls and peered closely at the clasp, then tapped one of the beads against his teeth and nodded. “Would you like it delivered?”
She shook her head and he swathed the statuette carefully in a clean rag. It was small enough to slip into her reticule in place of the pearls.