Iron bar

The Iron bar is a free-to-play Old School RuneScape item — “It's a bar of iron.”. Its Grand Exchange buy limit is 10,000 per 4 hours. Right now it buys at 141 gp and sells at 144 gp — a net margin of 1 gp (0.7% ROI) after the 2% Grand Exchange tax of 2 gp. High alchemy yields 16 gp.

To flip it, place a buy offer near 141 gp and a sell offer near 144 gp; the spread minus GE tax is your profit. Confidence figures are model estimates from live OSRS Wiki prices, not guarantees — flip responsibly.