Wood prices change all the time and the cost of a similar board will be different in different places. The only way you are going to get accurate job costing is to contact an actual local supplier. You have to ask the right questions in order to get accurate pricing of the stock you are looking for.
When you speak to a sales person you need to state the following:
First the species you are looking for: ash, red or white oak , walnut, beech etc. Then you need to give them the thickness (4/4, 5/4 8/4 etc.) The species available at a sawmill are generally localized to species they have access to, so if you go to a retailer, you'll find a larger, more varied selection. Also, if the material is to be purchased at a mill, you may not be able to pick and choose (this is called log run), you take what they pull off the stacks. At a full retailer you are more likely to be able to pick and choose stock within reason
Next, the grade of lumber you are looking for: FAS (first and seconds) is a good, general furniture and cabinet grade designation. I suggest that you try for this designation. If the stock is called out as No. 1, 2, or 3 common, be aware that there is cost savings in these grades, but with a trade off: you are going to have to work harder to get clear pieces of stock, by cutting around knots or other defects. This is an option, especially if you are building smaller projects.
Next is the way you want it cut ---flatsawn, rift or quartersawn. The price will vary according to the way the stock is cut.
below is a Wiki article explaining most of this in detail
This one is very important: is the stock kiln dried, and if yes, what is the average moisture content ?
Cheap lumber many times equates to green (fresh cut) stock, no drying done at all, or air dried, and if it has been air-dried, you should ask for how long. It can take upwards of a few years to get workable stock, and even then it may not be as stable as kiln dried stock.
Price is a function of all the above components, as well as the fact that the price will vary literally from week to week due to it being a commodity traded on the open market. Furthermore the quantities you require will vary by the total amount of stock you are looking to buy. for instance if I buy a full unit 1300-1500 BF from my supplier the cost is about 25% less than if I buy 50 BF. Therefore it is virtually impossible to give you an accurate representation of the cost per BF.
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