Figuring out Rise of Industry was so much fun that I ended up decompiling the game, ripping out all of the assets and looking into the code to figure out how things work. The project can be found here on https://github.com/mickvangelderen/rise-of-industry-calculator.

Basically, I was interested in what the Return of Investment (RoI) of producing certain products is. The RoI is the ratio between the profits and the cost to create the buildings. A high RoI means that profits are large compared to the initial investment. If we want to outcompete the other players (AI), we will want to grow our economy faster than they do theirs.

The results of this investigation are basically that:

• The RoI for most products is pretty close to each other. This is because the developer bases the price of products on the building upkeep, which is based on the building cost.
  
• The cost of transportation for valuable goods is the same as for cheap goods. This means that relatively, cheap goods cost more to transport. This affects the profits you can make with cheap goods and thus the RoI.
  
• Warehouses, trains, boats and zeppelins theoretically provide cheaper transport over long distances. However, the dispatching costs per vehicle are quite high, products arrive in bursts, they add to the investment costs, they require upkeep, and they take up space.
  
• Loans are cheap. There is no penalty for refinancing loans (paying one off and getting a new one). The interest for a loan is shown for the entire period. The longest loan period has the best interest rate. To keep the principal and the interest low, always pick the longest period.
  
• There is no reason you can't sell to cities outside of your territory, other than the price of transport being too high for cheap items (< 10k).

I play like this:

1. Pick a big territory that can be connected to 2-3 other towns by road efficiently.
   
2. The first 2 of the free techs go into research speed, the last into a production building I need.
   
3. Build production for high price modifier items costing > 10k. Move things around manually.
   
4. Research more production buildings.
   
5. Repeat 3-4 until you run out of money, take a loan to build more.
   
6. Repeat 3-5 until you run out of loans, attempt to pay off a small loan and take a bigger one.

Within 4-5 years you can buy out all the competition and have the map to yourself. This is not very fun, but figuring out what is efficient surely was!