Hold L and press C-up or C-down to zoom in and out. 
Its really helpful because its hard to see sometimes. 
Oddly, this was omitted from the game manual. 





Smart Building
Just to let you know, it is much smarter to build two 
regular power plants instead of one advanced. This is 
because it is $100 cheaper, and they have better defense 
than the advanced power plants. 





Sandbag Trick
To build things away from your base, use sandbags in 
a chain. This works with any building. You can use 
this trick to place your buildings in an enemy's base.