On how to unplug it specifically. Do chemicals work? I saw this one product, Septicare, as well as a few other, but unsure if they work. To repair/replace, I'm looking at anywhere between $2500 to $10,000. Any advice would be appreciated.
If your leach field is clogged you will have to dig a new ditch, new line, and refill it with gravel, in other words, start over. If you are having septic problems you can pump it out, and feed it regularly to minimize future problems.   The state laws in Colorado are massively strict if they find out you are having problems you will probably be required to have it fixed properly. Which equates to "costs a lot" no matter how you look at it!
Seems dubious. It wouldn't be enough to clean out the lines and the rock. It would have to somehow clean out the soil as well.
You may want to consider selling your house and moving back to the city...where they have pipes. I had to replace my entire septic system @ $22k. I too thought that I had leach line problems.
Based on what the septic tank guy said & what I see, I think my issue is with the leach system...hopefully that's all.