Plots can be sold and given to your residents. To put a plot for sale, type /plot forsale <price of the plot> while standing inside it. By default, the plot price will be set 0. Residents can then buy the plot by typing /plot claim. If the plot has a price, the amount paid will go to the town bank.
You can change the default price for newly set-for-sale plots with /town set plotprice <price>.
The owner of a plot can control who can access it by typing /plot set perm <group> <permission> [on/off] while standing inside it.
friend - players on your friend list. You can edit your friend list with /res friend.
resident - players from your town.
ally - players from your town, nation and allied nations.
outsider - players not from your town, nation or an allied nation.
build - controls whether a group can build in your plot
destroy - controls whether a group can break blocks in your plot
switch - controls whether a group can use chests, hoppers, furnaces, doors, dispensers, etc.
itemuse - controls whether a group can place/destroy minecarts, use buckets and bone meal, etc.
For example, /plot set perm build ally on would allow players from your town, nation and allied nations to build in the plot you are standing in.
If you want to control permissions for all your owned plots, use /resident set perm <group> <permission> [on/off]
Mayors can control permissions for all unowned plots with /town set perm <group> <permission> [on/off].
Plots can be of different types, which have unique functions. You can change a plot's type by typing /plot set <plot type> while standing in it.
default - the default plot type. All plots are default when first claimed. Non-default plots can be made default again with /plot set reset.
shop - designates a player shop area. The plot will appear red on the map.
arena - arena plots have PvP and friendly fire enabled at all times.
embassy - if for sale, embassy plots can be bought by any player, even if they're not a resident of the town.
bank - designates a bank, which allows you to deposit and withdraw from your town and nation banks.
jail - designates a jail, where players will be sent to if imprisoned - see the section on ranks.
farm - designates a farm, where the only blocks that can be placed and destroyed are crops.
wilds - designates a semi-protected wilderness plot, where trees, flowers, mushrooms etc can be broken but all other blocks cannot.