To prevent market crashes for nanban goods AngelGlass who is a real UWO veteran since beta release made the following suggestion:

Before selling nanban goods you crash the market deliberately with another type of good than what you want to sell. Thus as the market is already crashed it cant crash again on the precious goods you want to sell for another 3 hours. The same goes for spice sales of course.

The best trade good for crashing markets deliberately appears to be gold. Normally 50 or 100 gold should suffice to crash markets and there is a fairly low risk of ruining another French player’s sale of high priced goods since it rarely occurs that traders bring precious metals from East Asia or the spice islands.

Newbies may find it harder to crash markets due to low skill ranks and also less cargo space to carry “crash goods”. With low quantities to sell you dont need to bother. If you get help /trade goods to sell from advanced players in order to raise your trade lvls ideally the advanced player should crash the market for you if the quantity is large enough to warrant the extra work and cost to crash the market.

Before crashing market check what market keeper says. If he says “…prices of … are plummeting” then the market is already crashed.

For all those sailing without provisions this may be difficult as you dont have free cargo space for crashing goods. Here you have 2 options: either ask a company mate or friend who is in Europe to crash market for you or do it yourself with an alt if you have one.

I spoke with the directors of BlueMoon, Tabernacos and AgeofDiscovery about this topic. The goal is to get good sales profits for all French players.