How to flip Amethyst arrow(p++) in OSRS

Flipping Amethyst arrow(p++) on the Old School RuneScape Grand Exchange currently makes about 87 gp profit per item after the 2% GE tax: buy near 645 gp (the instant-sell price) and re-list near 746 gp (the instant-buy price).

• Buy at (instant-sell): 645 gp
• Sell at (instant-buy): 746 gp
• Margin after 2% tax: 87 gp (13.49% ROI)
• Buy limit per 4 hours: 11,000
• 24h volume: 89,544 (very liquid)
• Max profit per limit cycle: 957,000 gp on 7,095,000 gp of capital

The flip, step by step

1. Place a buy offer at or just above 645 gp (the current instant-sell price).
2. Wait for the fill. Amethyst arrow(p++) is very liquid right now, so offers usually fill within minutes to a quarter hour.
3. Re-list at or just below 746 gp (the current instant-buy price).
4. The GE takes 14 gp tax (2%) per item when it sells, leaving 87 gp profit each.
5. Repeat up to the buy limit (11,000 per 4 hours), a full cycle is 957,000 gp on 7,095,000 gp of capital.

Margins move constantly. Re-check the live Amethyst arrow(p++) numbers and price chart on GrandExchange.com right before committing.