A large share of your foothills clicks are people shopping a cabin two hours west
Location targeting in Colorado has a specific failure mode: a Denver device searching for work that will happen somewhere you do not drive.
Plenty of Front Range households own or rent property west of the foothills. When one of them searches for a bathroom remodeler, the platform sees a metro location and serves your ad. The job is two hours up the interstate and you are never going to install it.
Set targeting to people in your locations rather than people merely interested in them, then say the service area out loud in the ad and again on the landing page. Naming Denver County, Jefferson County and Arapahoe County in plain text costs you some clicks, which is the entire point.
Read the search terms report weekly and add mountain town names as negatives when they appear. It is a small chore that never finishes, and skipping it is how a budget funds sightseeing.
Apply the same discipline at the north end. Boulder County searches will show up inside a metro campaign, and if you do not work up there they should be excluded rather than paid for out of habit.