I would call a few plumbing contractors and ask if they do this kind of work. If the utility works like ours, the plumber runs the trench, pipes it inside and outside, and calls for an inspection and hookup. I can't imagine it being that expensive, even in California! I just ran a line 280' to our gas well. Borrowed equipment and labor from a friend. I bought the pipe, two regulators, furnace conversion, inside piping, and meter for under $1500. Strangely, When the gas company buys gas from you, they make you buy the household meter. The piping is not a DIY job, I'm in the trade, and had help from a master plumber.