There are various things you can do to save money, like finding free/cheap poles from utility companies or similar, but in the end the price of the rhizomes doesn't change and that's a big chunk. Everything else is based on your aversion to risk. Go with 1/4", 5/16", or less depending on how sure you are of the rest of the design. I like turnbuckles because we are constantly adjusting but you could do the same with a comealong and wire gripper. Likewise, we get rid of the cost of the W clip but replace it with a wire running a foot off the ground to tie the twine too.
In the end figure on $10k for set up (maybe a little less if you find deals) plus cost of well (if needed), tractor or pickup, another $1k for drying (2nd year) and anything you need for harvesting. On going, there is weeding, nutrients, pest management, etc. Figure 20 hours a week the first couple of years to get it established plus another 5 to 10 hours a week explaining the question, "What you got going on here?"