Black longsword

The Black longsword is a free-to-play Old School RuneScape item — “A razor sharp longsword.”. Its Grand Exchange buy limit is 125 per 4 hours. Right now it buys at 267 gp and sells at 656 gp — a net margin of 376 gp (140.8% ROI) after the 2% Grand Exchange tax of 13 gp. High alchemy yields 576 gp.

To flip it, place a buy offer near 267 gp and a sell offer near 656 gp; the spread minus GE tax is your profit. Confidence figures are model estimates from live OSRS Wiki prices, not guarantees — flip responsibly.