Pre-orders
General Concept
Pre-orders don't work the same way on Arch & Archwar than on other servers. For A&AW, it costs 1 turn to set a pre-order, and with a maximum of 1 pre-order with a cap of 5 items (e.g.: 5 ash of invisibility) while on the others there is an unlimited amount of pre-orders possible, for free, which makes it able to buy things on the BM without spending a turn (which on the other hand boosts inflation on servers such as guild/blitz greatly).
subtlety
A question was what would happen if two (or more) persons has set a same pre-order (same item, same price); at first it was thought it was randomly picked inbetween pre-orderes, but it isn't, actually the first one to have set the pre-order gets it. Meaning, if you see an item getting pre-ordered at 20m, don't set the pre-order at 20m too else there's strong chances that you never get it if the person has set for "999" items, you would have to set it a bit higher.
Discovery made through experiments with a ~99.98% confidence interval by Magewarfelix, Zalithian and Laanders