Are used to trade resources with your neighbours.When you are running low in goods and you have enough coins you can trade the coins for goods with your neighbours using the train.After you unlocked the train ,click on the train platform and a pop-up named Train Schedule.
Here you can choose to sell or to buy goods .To do so choose from the list the quantity you need and click Send Train.
When the train is going to come back you will see a traffic light with the message Click Me.What do you do now :) ?Yes you click on the message and you will receive what you needed (coins or goods).
Sometimes you will see again the traffic lights even if you didn't send a train.This means that one of your neighbours sent one .If you like the offer you can trade with him even smaller amounts by clicking buy button and choosing the amount you wish to trade.If you aren't interested in the offer click decline and move on :)
Franchises guide :
The Franchises can be unlocked by completing quest or with cash .If you want to build one in to a neighbour’s city you first need to have the business already build in your city.After that you go in a city , find an empty plot like this one in the picture and click on it.
Then you will see in a window all the business you own.Now choose whatever you want ,place it and wait for your neighbour to accept it .After they accept it , you will see two new icons on your screen.From there you control your franchises - you can supply them with goods or expand them .By clicking on the other button you will receive your HQ building in your inventory and then place it in your town.
End of part 3