How to Make Money (Useful Tips)
Money in realistic mode is best done with clothing factory, people will argue otherwise, but the simple truth of 5 combined factors make it undeniably the best building and overpowered.
Each factor on its own is, of course, not overpowered.
1: The clothing factory has a cheap resource input (Crops). vs output good (Fabric.)
Result: this makes the profit ratio skewer massive upwards.
2: It has a low worker count to maximum effectiveness.
Result: The factory can be run with foreign labour or a tiny support network on realistic, which means time to pay off loans (if starting on hard) is really quick, compared to almost all else.
3: Crops can be automated later on, no other resource can which is initially available.
Result: Removal of trucks/trains at the border bringing in goods lowers costs and makes it even more viable, but it is optional (as you add fuel costs and building costs to the farms and harvesters.)
4: Small blueprints of building, and low emissions..
Mean that it’s a relatively “Safe” factory to have closer to the town, within walking distance of the better paths which ensures a constant stream of workers from homes.
Result: Constant stream of high value goods.
5: Low quantities of product as product is slow to make.
Result: High ruble per ton, low amount of export trucks, no need for railway.
The best approach to expanding in my opinion is to build the industries with the lowest vehicle requirements and the best returns on investment costs:
Early on this is the clothes factory, fabric factory, distillery, explosives factory, food factory, nearby oil wells, and incinerating hazardous waste.
With a little research, you can do chemical plants, electrical component factories, bauxite mining/processing, uranium processing, tourism, mechanical component factories, and fuel/bitumen refining.
Construction material industries should only be built to free up customs house traffic for exports, as they all have low profit and tend to need a lot of transportation to fully exploit. Gravel and boards are good first cases because you can set them up with less than 20 workers and 50,000 rubles each, including vehicles. Concrete and asphalt plants might also be built further from a customs house to expedite construction times.
Power production is questionable, because although power plants cost a lot and will take well over a year to pay off (compared to just exporting the coal/oil), they eliminate a somewhat costly import of power and a good chunk of the transportation needed to move coal or oil to a customs house. I usually recommend building it once you start using a decent amount of power to eliminate the cost of importing power, as several thousand MWh a day at a ruble each add up quick.
Coal/iron mining is not that profitable compared to the capital costs, and should be treated like power. Build it once you have a decent cash flow going and are ready to expand to steel or at least to replace your coal, brick, and cement imports.
Steel, aluminum, and vehicle factories all give good income, but require a lot of transportation or investment in money or research.