Just for fun, I ran some numbers based on building production and requirements and such. I based production figures on a per-building number, which equals the number of buildings you need to produce that resource. For example, if you want a bank producing money (assuming all equal level buildings) you also need a fifth of a power plant to produce the power and 15% of a coal mine to get the coal for that power, so the total buildings involved in that one bank producing is 1.35. This means 20 banks needs 4 power plants and 3 coal mines to support them. I also calculated the total cost of the buildings in cement/lumber/steel.
Anyway, using per building production numbers and assigning prices based on the amount of buildings required, adjusted a bit to be nice round numbers and to give really expensive buildings a higher product value, I came up with the following price chart (all standardized to the value of money). Each price is per 1000 units.
Resource Price Income* Hours till breakeven**
Money 1000 592.59 280.75
Lumber 90 432*** 73.22
Cement 90 432*** 73.22
Coal 70 560 141.47
Steel 1600 595.35 224.9
Rubber 3000 576**** 62.78
Rare Metal 1600 480 165.05
Fuel 2700 557.47 278.16
Food 800 480 75.34
Uniforms 50000 531.91 211.3
Ammunition 1000 595.16 280.57
Horses 27000 486***** 74.41
*Money value income, per hour per building, using numbers from level 20 buildings.
**Based on the average costs of the buildings divided by the per-building hourly production.
***Base value at 100%, 561 on 30% bonus terrain.
****Rubber from rubber farms on jungle. Synthetic rubber factories would be a measly 246.15.
*****Based on 120% production on plains/savanna.
I mostly did it to sate my own curiosity, but it does give a pretty good idea of how resources relate to eachother and where to set prices on things. It also highlights that fuel is really, really expensive to produce - making shipment by plane/truck a very expensive endeavor. With the ease of getting coal, trains are the obvious choice for cheaply hauling resources around.