How to flip Super defence(3) in OSRS

Flipping Super defence(3) on the Old School RuneScape Grand Exchange currently makes about -40 gp profit per item after the 2% GE tax: buy near 2,309 gp (the instant-sell price) and re-list near 2,315 gp (the instant-buy price).

• Buy at (instant-sell): 2,309 gp
• Sell at (instant-buy): 2,315 gp
• Margin after 2% tax: -40 gp (-1.73% ROI)
• Buy limit per 4 hours: 2,000
• 24h volume: 272,882 (extremely liquid)
• Max profit per limit cycle: -80,000 gp on 4,618,000 gp of capital

The flip, step by step

1. Place a buy offer at or just above 2,309 gp (the current instant-sell price).
2. Wait for the fill. Super defence(3) is extremely liquid right now, so offers at fair prices typically fill within minutes.
3. Re-list at or just below 2,315 gp (the current instant-buy price).
4. The GE takes 46 gp tax (2%) per item when it sells, leaving -40 gp profit each.
5. Repeat up to the buy limit (2,000 per 4 hours), a full cycle is -80,000 gp on 4,618,000 gp of capital.

Margins move constantly. Re-check the live Super defence(3) numbers and price chart on GrandExchange.com right before committing.