The PCs enter a new town. It's far away from any major cities but close enough to a well traveled road. The town sees its fair share of visitors, but there is no reason for any to stay long. It has a modest population that mostly takes care of themselves.
There is a farrier, because horses throw shoes and need shodding.
There is a wainwright, because wagons and carts on the road need fixing.
There is an inn, because weary travelers need a place to say.
There is a cobbler, because it is the most common skilled profession. Also, goodwives can spin, sew, and mend clothes - but not shoes.
There is a blacksmith, because farm tools will need to be made or repaired.
There is a priest in a temple or shrine, to take care of the towns and travelers spiritual needs.
There is a miller who grinds grain and collects the local taxes. Because of the later, the Miller is not well liked.
And that's about it. A slightly larger town might have a carpenter, tailor, thatcher, tanner, two inns instead of one, two cobblers, etc. But in a true rural area, most people take care of their own home construction and repair - with the assistance if needed of neighbors and family (usually the same thing). About 50 farm families, including some sizable extended families with multiple households living together live in the immediate environs of the town and farm the surrounding 1200 acres or so and think of themselves as belonging to the town even if you cant' see their house from the town. There are also a dozen families of woodcutters, shepherds, swineherds and other rural professions. Lots of households are pulling double duty of some sort, but haven't yet got enough business as chandlers, dyers, fullers, cheesemakers, or whatever to give up farming as the primary livelihood. As the towns population expands, branches of these families will take up full time professions (often because the land is running out).
Every week or two, a travelling merchant will stop in the town. The town may have a regular Faire day when merchants know to come to the town because the farmers will come from the farms to buy things the town can't provide. This may involve a lot of barter, with the merchant trading for things he knows he can sell at a profit in the city, because coin in these parts are scarce. Depending on what the local products are the town may have a Cooper to make and repair barrels.
Every few weeks a reeve appointed by the king may stop in town to see how things are going. But most complaints, civil disputes and justice go through the local Lord (a hereditary Knight or a Baron), who has a manor around here with 6-12 servants for his family.
Every few months, a tinker will stop in the town, offering to repair pots.
Seasonably, the town may see a travelling bodger set up shop.