Copay

Derail Valley comes with insurance included. It works on the copay principle. This means you pay up to the copay amount, and once you reach that, the insurance pays all remaining costs, and the copay period starts again. You can check your copay as well as the amount already paid in the career manager. Any money spent in the "Fees" section of the career manager (or in Manual Service Stations) counts towards your copay. This includes things like emissions tax, maintenance for your locomotives, cars damage or cargo damage.

The copay starts at only 100$, and increases as you buy new licenses. Not every license increases the copay. You can use the print button in the career manager to get a preview of the license, which shows by how much your copay increases. The copay increases quickly as you buy licenses, so if you want to try something risky, do so in the early game, or make a backup of your savegame.

Strategy

There is no way of lowering your copay, and fees for jobs are pretty much guaranteed to exceed the 100$ amount you start with.

This means that if you plan on getting a certain license combination (for example Manual Service, Long 1, and Hazmat 1), you may want to wait with buying those licenses until you can afford all of them at once.

Example

Let say your copay is 1'000$, and you have two fees to pay, one is 3'000$ and one is 4'000$. Trying to pay for any of these fees has you only pay for the copay amount (1'000$), and all outstanding fees (6'000$) will be cleared, including those you haven't made any payment towards yet.