Fencing Bylaw
In most cases back and side yard fence heights for residential properties are restricted to a maximum height of 213cm, or seven feet. Front yard fence heights are restricted to a height of 1m. Fences may not be of sharp materials, including chicken wire and may not be electrified. The front of the fence is to face neighboring properties or the street. These height restrictions do not apply to hedges or other plant material.
Accessory Buildings
Sheds, pool houses, hot tubs, etcetera.
There are a set of guidelines within the bylaws which apply specifically to accessory buildings. These apply even to buildings for which you are not required to obtain a building permit for.
Only two accessory buildings are permitted on any lot.
The total permitted coverage of any yard is a maximum of 50% of the total yard area. This is calculated based on the outline of the building's walls, rather than the outline of the roof.
The maximum height of any accessory building is 4.5m.
Thinks that you may call city to ask them : is it still can be setup if the height of your neighbor's accessory building could affect your living?
On the other side, looks that your neighbor's accessory building is over 50% coverage --- The total permitted coverage of any yard is a maximum of 50% of the total yard area.
Also, I remember that if the deck is not on the ground with some centermeters high, it needs to have a city permit.