Buildings
Constructing buildings on your land will be necessary for long-term success and survival. Constructing buildings does take time. The number of buildings you can create in one turn depends on the number of construction sites you own. Note that each construction site takes one turn to build regardless. Also, spending turns is rounded up; for example, spending 5.5 turns on construction will actually consume 6 turns.
Building Descriptions
Enterprise Zones Enterprise Zones help to increase the productivity of your population. Your total tax revenues are dependent upon the number of people you have, how much they earn each turn (Per Capita Income), and your tax rate. These buildings will help to increase the maximum Per Capita Income your people can achieve.
Residences While people build homes on all the land regardless of what else occupies it, Residences are areas specifically designed for housing. As a result, they allow you to house a great deal more people than any other type of land.
Industrial Complexes There are two primary ways of building a powerful military. The first is through a simple purchase. Industrial Complexes provide an alternative, automatically constructing a few units each turn.
Military Bases Having military bases allows you to train troops and purchase equipment at a lower cost. This provides you the ability to focus on generating income and then buying forces rather than building them. In addition, Military Bases help keep your forces in good condition, helping to reduce maintainence costs.
Research Labs Researching technology takes time. Simply put, the more R&D Labs you own, the less time you will need to spend to develop new technologies. Because technology is vital to success and turns are a limited resource, research labs are important to quick growth.
Farms While unused land produces a little bit of food each turn, building farms sets aside specific areas for food production and thus makes much more efficent use of those areas. As you build other structures on your land, farms will be vital to supplying your people with food to survive.
Oil Rigs Oil Rigs are used to drill your lands for Oil, which is used in combat. Each Oil Rig will produce approximately 2 Barrels of Oil per turn.
Construction Sites Like R&D, constructing new buildings takes time. Having these sites will help you to reduce the time consumed in creating a new building. Construction sites each require one turn to build, regardless of other factors.