The many settlements from Pathfinder Campaign Setting: Towns of the Inner Sea show smaller locations throughout the world of Golarion that are perfect for telling stories on a small scale. Radically changing the political or cultural face of a large city make be a massive ordeal taking up most of a campaign, but doing so in a town might take only the course of one adventure and happen at a lower level. The Varisian town of Ilsurian is a primarily peaceful place, but the dangers around the town could close in at any moment!
Ilsurian was founded by the Chelish expatriate Ilsur, and their independence from the tyranny of that diabolic state gave the town their identity. They pride themselves on their independence and discipline, and everybody who comes of age in the town knows how to use a weapon. Think of them like fairweather patriots: they talk a good game and know a few things, but they're no soldiers.
If you want a good kick-off to a campaign that starts in Ilsurian, Pathfinder Module: Murder's Mark takes you there, and you can use the description in Towns of the Inner Sea to flesh out the adventure further. And not to say too much about the plot of that adventure, but it's possible some real estate might free up in town for the PCs to snag on the cheap so they can set up a home base...