Before or after building a house and activating an effect on their turn, a player can choose to create one of the two available roundabouts.
Choose an empty house’s box, draw a circle and a dot inside it where a house number would go, and then build estate fences to the left and the right of the roundabout.
The roundabout divides the street in two.
Therefore, house numbers may start over directly to the right of the roundabout.
Players can use numbers 0-17 to the left of a roundabout, while also using numbers 0-17 on the other side.
Cross off the top-most space on the roundabout column. The first costs 3 points and the second costs 5 points.
At the end of the game, subtract the smallest, unchecked number from the final score.