One you figure out the setting you want, it's eeasy peasy. And it comes with very clear instructions.
Basically you:
1. Rezz the server in a region (The Kiosk and map are optional) and configure it (i.e. currency, how many weeks can people rent, the "default prize", "default maximum prims".
2. You go around the sim and rezz the rental boxes close to the individual parcel you want to rent (you have to edit+link>drag an invisible prim inside the parcel). In the individual rentalbox you configure the name of that parcel, type of rent (via land ownership or group), whether it uses default server price and prims, or you set individual ones). You can also add an picture of the lot that will be showcased on the kiosk.
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