What's the simplest system we could come up with for trading goods by sea that would still have some of the flavor of the real deal? I figure some of you are very knowledgeable about this stuff (looking at you richard).
I'm thinking 3-4 tiers of. More risk = more return. More risk will mostly = ports farther away. Maybe have the player roll each session we play to check on the trade voyage's fate.
1. What should the probabilities of succeeding be for low, medium, high risk? If you stick with a single d6 and have the roll be 4-5-6, 5-6, or 6, that would be a fifty-fifty chance of losing a cargo even at the lowest risk.
2. What returns should I be looking at? I'd like no chart necessary, so numbers like +10%, +25%, +50% are more attractive, because I can do them in my head. I have no idea if those are way too much or too little.
If we stick to general rates of return based on distance, we can decide later what ports have what goods and just plug them in and you could always layer shortages and rarity on top of the basic system bones.
Yeah, I realize this could ruin everything and let people make their fortune without needing to enter dungeons. But investigating the loss of a vessel, or even traveling on your own trade vessel à la Sinbad, is right down my campaign's alley.