How to flip Ahrim's robetop in OSRS

Flipping Ahrim's robetop on the Old School RuneScape Grand Exchange currently makes about -7,503 gp profit per item after the 2% GE tax: buy near 1,013,375 gp (the instant-sell price) and re-list near 1,026,400 gp (the instant-buy price).

• Buy at (instant-sell): 1,013,375 gp
• Sell at (instant-buy): 1,026,400 gp
• Margin after 2% tax: -7,503 gp (-0.74% ROI)
• Buy limit per 4 hours: 15
• 24h volume: 1,150 (liquid)
• Max profit per limit cycle: -112,545 gp on 15,200,625 gp of capital

The flip, step by step

1. Place a buy offer at or just above 1,013,375 gp (the current instant-sell price).
2. Wait for the fill. Ahrim's robetop is liquid right now, so expect fills within the hour at reasonable prices.
3. Re-list at or just below 1,026,400 gp (the current instant-buy price).
4. The GE takes 20,528 gp tax (2%) per item when it sells, leaving -7,503 gp profit each.
5. Repeat up to the buy limit (15 per 4 hours), a full cycle is -112,545 gp on 15,200,625 gp of capital.

Margins move constantly. Re-check the live Ahrim's robetop numbers and price chart on GrandExchange.com right before committing.