I have a lead on some low priced lumber. There is quite a bit, and I am not used to purchasing in large quantities. I am told there is about 600 BF of one species and 2,500 BF of another. I want to be sure those numbers are accurate before I make a purchase. If the piles are neatly stacked, with little space between them, I can measure length, width, and height and simply do the math. If is neatly stickered, I can probably make a reasonable guess about that too. What I want to know is how this is done by those of you who have done it. Are there any factors that you use to adjust the amount to get it more accurate? For example, do you make a rough measure of the size of the pile and do something like take off 10% for airspace? Any advice would probably be helpful.