How to flip Armageddon cape fabric in OSRS

Flipping Armageddon cape fabric on the Old School RuneScape Grand Exchange currently makes about 339,319 gp profit per item after the 2% GE tax: buy near 3,090,681 gp (the instant-sell price) and re-list near 3,500,000 gp (the instant-buy price).

• Buy at (instant-sell): 3,090,681 gp
• Sell at (instant-buy): 3,500,000 gp
• Margin after 2% tax: 339,319 gp (10.98% ROI)
• Buy limit per 4 hours: 5
• 24h volume: 137 (moderately traded)
• Max profit per limit cycle: 1,696,595 gp on 15,453,405 gp of capital

The flip, step by step

1. Place a buy offer at or just above 3,090,681 gp (the current instant-sell price).
2. Wait for the fill. Armageddon cape fabric is moderately traded right now, so fills can take an hour or more, patience pays here.
3. Re-list at or just below 3,500,000 gp (the current instant-buy price).
4. The GE takes 70,000 gp tax (2%) per item when it sells, leaving 339,319 gp profit each.
5. Repeat up to the buy limit (5 per 4 hours), a full cycle is 1,696,595 gp on 15,453,405 gp of capital.

Margins move constantly. Re-check the live Armageddon cape fabric numbers and price chart on GrandExchange.com right before committing.