Saving money by staying at home.

Much time has passed since I last spoke to you of my son, and I fear the relationship between us has only soured. He has abandoned our family quest to create the ultimate dwarf; no longer does he seek adventure in the lost mines and vaults of the world. Instead, his party have set up a camp by one of the roads leading from my realm to the adjoining human lands, and are charging a toll to all who pass.

I would not call what he is doing banditry; those who refuse to pay are simply turned away to seek another road, and the mechants I have spoken to do not consider the amount he demands unreasonable. Besides, he is my own flesh and blood, and so I have no desire to lead my army against him. Nevertheless, I would like him to stop, and return to more dwarven ways.

Of course, I cannot hope to persuade him to stop without first understanding what he stands to lose by stopping, and so I must ask: How profitable is charging a toll on a road? Is there some formula for calculating the amount of traffic on a road, and from that the amount of gold that could be earned as tolls in a given month? I'm not sure how to apply the usual 33:1 investment:profit-per-month ratio, as most of the costs of charging tolls are ongoing.

Please help me, Autarchs!

(Real talk time: The players in the campaign I'm running have two noteworty opportunities to earn gold by charging tolls. The first is a magic portal they've built a stronghold around, with a class IV market a few days travel away on one side and a class III market a similar distance away on the other, each with very different trade modifiers; and the second is a gatehouse at the east entrance of a megadungeon, which was formerly inhabited by kobolds who made a living by charging a toll to beastmen who wanted to enter or leave. In either case, I have no idea how much they should be able to earn through tolls, and am sorely in need of guidance, as they've been making plans to start charging tolls in the near future.)

GMJoe - Given what you've said an appropriate toll would be 6-12gp, with a minimum toal of 1gp per load. I will assume 10gp. They could also seek to levy a customs duty of between 2% and 20% of market value. Since they are just a tollgate and not a full market, I think the custom duty would be on the low end - 5% at most.

There will be (2.5 merchants) x (5 loads) x (market impact 10) = 125 loads of merchandise traversing the tollgate from the Class III to Class IV market each month. The average value of the merchandise will be (125 x 300gp) = 37,500gp. 

The revenue potential will therefore be (25 merchants x 10gp / merchant) = 250gp from tolls and (.05 x 37,500gp) 1,875gp from customs duties, for a total of 2,125gp.


Nifty! THanks for the information, Alex.

I'm curious, though - what's "market impact" and how is it calculated?

Market impact is a new factor I introduced in AXIOMS Issue 3. Quickly summarized, the number of merchants listed for a market is only 10% of the total number of merchants. The system assumes you aren't making an enormous "impact" on the market. By dialing up things by a factor of 10, we reflect the full commerce going on in the city.


Nifty! Thanks for the explanation.

I must confess I haven't been following Axioms... I bought a year's subscription on drivethruRPG shortly before new issues stopped being released, and haven't really felt up to buying more since. Even so, it's gems like this that tempt me to buy the back issues...

Oh, no! Did you get all 4 of the past issues? I was never very happy with how that subscription service worked so I shut it down.

If you're missing Axioms content you paid for, let me know.


I didn't get all four past issues, though I did get a couple of them: My DriveThruRPG library has downloads for Axioms 1 and 4. I could've sworn I had a download for Axioms special edition as well, but it doesn't seem to be in my downloads library any more, for some reason, and I can't find it on my hard drive, so maybe I've gotten confused.

That said, wouldn't a subscriuption normally only include issues released after the subscription was purchased? I can no longer remember what was supposed to be included in a year's subscription, nor exactly when I bought it (I think it was probably around may of 2017), but I vaguely recall thinking it was cheap and being surprised that it also included certain back issues, so I'm guessing I got enough issues to make the purchase worthwhile.

In any case, you needn't bother yourself about this. It's a pretty minor issue, all things considered, and I'll probably get around to buying the back issues eventually.

GMJoe, the DTRPG subscription is very wonky which is why I stopped using it. Anyway, if you're missing stuff you paid for hit me at anytime and I'll get you what you need.

Alex, Are the tolls and customs duties you shared for the entire route or per leg? I assume it’s the former. However, it would be quite realistic for every domain ruler between two cities to charge passage fees. How do you recommend adjudicating multiple rulers all trying to get a cut? Is the “reasonable” solution that they divide up the total value, or do they each charge up to the total with an added cost to consumers?

For a real world example, how would you calculate tolls and duties between 13th century Frankfurt and Wurzburg? Or, how about between two major nodes on the Silk Road?