H.D.
We had our foundation done last year. I had 6 quotes from various companies. Don't waste your time with Olsham. They are good but so overpriced. We and some friends of ours went with PermaPier. Very impressed. They weren't the cheapest (probably 3rd cheapest) but we just felt comfortable with them. Check the companies out on the better business bureau. It's alot of money so you want it done right. Make sure it comes with a transferable warranty and get an engineering report. Good luck.