Instructions
Power Deals
Select the power line tool and drag it until it is outside the city grid; this will create a power deal with the neighboring city.
Select the "Budget" menu, select "Deals" and set the power deal to "Sell" to sell your power to the neighboring city. However, you can only do this if the neighboring city is low on power and your city has a surplus of power.
Select your "Budget" menu, select "Deals" and set the power deal to "Buy" to buy power from the city you have a power deal with. Keep in mind you can only do this if you are low on power and the neighboring city has a surplus of power.
Water Deals
Select the underground pipe tool and drag it until it stretches outside your city borders to create a water deal with your neighboring city.
Select your "Budget" menu, select "Deals" and set the water deal to "Sell." You can only do this if you have a surplus of water and the neighboring city is low on water.
Select your "Budget" menu, select "Deals" and set the water deal to "Buy." Again, you can only do this if your city is low on water and neighboring city has a surplus of water.
Garbage Deals
Select the "Road," "Rail," "Highway" or "Seaport" tool and drag it outside your city's grid to create a garbage deal.
Select "Budget" menu, select "Deals" and set the garbage deal to "Export" to ship your garbage to a neighboring city. You may only do this if the neighboring can house your city's garbage as well as theirs while your city has no room for its own garbage.
Select "Budget" menu, select "Deals" and set the garbage deal to "Import" to accept garbage from the neighboring city. You may only do this if your city can house your garbage as well as theirs while they have no room for their own garbage.