Typically, you will receive 10-12gp of oak for every plank
Typically, you will receive 10-12gp of oak for every plank (which means you should set your buy price at 13-17 under mid) you do which may appear to be a bit low, but over time, you'll get more and RuneScape Gold more and more...before all you can imagine, you will be trading regularly 25,000 and earning 300k for each trade.
It will likely take you an entire week this, but it's one of those...