A flip is three moves: buy the ingredients through orders, craft, sell the result into somebody else’s order. Here it is end to end with round numbers.
buy 9 × iron ingot @ $100 = $900
craft 9 ingots → 1 iron block
sell 1 × iron block @ $1,200 = $1,200
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profit $300You put in $900 and got back $1,200. The $300 difference is the trade.
That is ROI
$300 profit on $900 spent is a 33% return. That percentage is what this site calls ROI — and it is only half the story, which is the next lesson.
What actually takes the time
- Fastplacing the order — a few seconds in game.
- Slowwaiting for players to deliver. Minutes, hours, or never.
- Fastcrafting and delivering the output.
The waiting is the real constraint, and it is why this site reports how much of an item has actually been seen moving rather than assuming an order summons any quantity you like.
Do not craft early
Wait until the ingredients are actually in your inventory. An order that has not filled is not a purchase, and the price you sell into can move while you wait.