They cost per the foot, but you need a geologist to determine how many and how close to each other. Like expensive cars, if you have to ask the price, then you can't afford it. They are very expensive to say the least. If you got the land for free, it still might not be a good deal. Also, you never know how far down they will need to go until you start. I remember when my dad built a building on what was just about a swamp because the land was given to him by the city. It would have been cheaper to buy land after they finished driving all the pilings. The road in front of the building was like driving across a earthquake area. Every day it got a new dip or pot hole.
