I keep seeing that book being mentioned. I had a guy come out and he builds ponds only. He actually does core trenches, and of course his quote is going to be 7-10k. I haven't seen it yet, but I'm sure it'll be in the middle. For that kind of money for a tiny pond, I'm going to wait for the first guy that wanted to dig it for 5500. Both own their equipment. I will not ever go with someone that needs to rent.
