Figuring out how much product you need,
Staining, you will need to know the square footage of the area you are staining. To get the square footage take the length in feet of the wall, multiplied by the height in feet.
Chinking, you will need to know the linear footage, the joint width and the depth of chink line you are going to apply. To get the linear footage you can measure each individually or measure one and multiply the total number of lines in that wall. Don't forget to subtract the windows and doors.