The links below will take you to charts for buying buildings that produce income every hour. The different types of buildings provide different levels of additional income and each one costs incrementally more and more. So it can be difficult to make sure you are building them in the most cost-effective manner.
These charts provide examples of how to build "equally" so you aren't overpaying for one type of building rather than building another. But the numbers from column to column are pretty far apart, so you should become accustomed to calculating "building equality" on your own. To do this, simply divide the cost of the next building by it's increase to income. The lower the number the better the value. Whichever building (of the same type) provides the best value is the one you should buy next. Many users use spreadsheets to help them do this automatically.
If you have no hero groups or wonders that provide a percentage bonus to income you can disregard the top six lines in each chart that start with a percentage. The charts were designed for players without an income bonus. But if you have a bonus, then you can find your bonus percentage in the lines at the top to see what each column's build data works out to be for you at your bonus level. The numbers for total income won't be rounded as nicely, but they can still be very helpful for planning.
The real value to these charts is long-range planning. If, for example, you want to reach an income of 5 million by level 50, the charts will tell you how much the total of those buildings will cost (9.78 Billion). It will also tell you exactly how many of each type of building to buy. Once you have your income up to 5 million, the charts will also tell you how much more it will cost to get to 6 million, 7 million and so on.
Because more types of buildings become available as you level up in the game, the build costs and equalities work differently based on the buildings available to you at your current level. So there are different groups of charts based on what buildings are available to you. Each group has three or four charts with eight columns per chart for 24-32 different income levels. Be aware that the jump from column to column may change as you move from one chart to the next in a given level.
Once you reach a level in the game where a new building comes available, you should first look at your existing buildings 'equality' and determine how many of the new buildings it will take to get it caught up with the others. For example, when you reach level 72 Hydro Plants become available. If your income is 6 million then you should have about 1800 Farms, 1100 Harbors, 700 Markets, 480 Banks, 360 Guilds, 270 Corporations and 195 Coal Plants. This is very close to the building numbers for the 9 Million (per hour) level on the Hydro Plants charts because you should now buy 125 Hydro Plants (income of 3.125 Mil) before buying any other income producing buildings.
- Harbor Level (7-15) - Income up to 2.8 Million
- Marketplace Level (15-18) - Income up to 3.5 Million
- Bank Level (18-26) - Income up to 4.5 Million
- Guild Level (26-31) - Income up to 6.5 Million
- Corporation Level (31-44) - Income up to 10 Million
- Coal Plant Level (44-72) - Income up to 26 Million
- Hydro Plant Level (72-100) - Income up to 48 Million
- Nuclear Plant Level (100-160) - Income up to 85 Million
- Hydrogen Plant Level (160-200) - Income up to 110 Million
- Space Solar Plant Level (200-220) - Income up to 150 Million
- Plutonium Lab Level (220-260) - Income up to 220 Million
- Armstrong Base Level (260-300) - Income up to 440 Million
- Space Mineral Stope Level (300+) - Income up to 1 Billion!!!