Step 1:
  
 Create a region with WorldGuard
  
 Step 2:
  
 Place a Sign OUTSIDE THE REGION! (Players can't remove them)
  
 Step 3:
   
  
   
   Line 1: [arm-rent]
  
 Line 2: the world of the region. If the region is in the same world it can be let empty
  
 Line 3: the name of the region
  
 Line 4: <the price the region should cost per extend>;<the time the region should be extended per click(you can use "s" for seconds, "m" for minutes, "h" for hours, "d" for days")>;<the maximum time the region can be expanded to(you can use "s" for seconds, "m" for minutes, "h" for hours, "d" for days")> 
  
or an autoprice
   Step 4:
  
 You are done. Now players can buy the region.
  
 You can now assign a regionkind to the region if you want, so players can find it easier and you can limitate it better.
  
 Use /arm setregionkind REGIONKIND REGION
  
 You can also mark the region as a Hotel, so players cant remove blocks that they haven't build.
  
 Use /arm sethotel REGION true
  
 You can also deactivate inactivityreset for the region
  
 Use /arm setinactivityreset REGION false
  
 You can also deactivate region restoring, if the region gets automatically resetted.
  
 Use /arm setautorestore REGION false
   
  
 And much more...