I lived for 15 years in a house with well water. The house was already old when we bought it and we never did any maintenance on the well. When we sold it, we noticed that the water pressure had become a bit lower than it was originally.
When we just moved in, we had the water tested and all values were OK, except that is was a little high iron values. I also had another test for radon once.
But we also had a big issue once. One summer holiday I had turned off the electricity of the pump and left it so for a few weeks. When we came back, the water stank. We then flushed bathtub after bathtub with water and that made it stink a bit less. We also started cooking the water and ordered a new test. It turned out that the water contained intestinal bacteria, som that could only survive for a few days. I don't know where this came from, because we lived on a steep hill with no houses above us. Maybe it came from our own septic tank on the other side of the house?
We than ordered a filter (working with light) that can be fitted into a kitchen cupboard. This way we only filtered the drinking water, but not all the other water. This worked well. When selling the house we mentioned the filter in the kitchen and the lower water pressure and mentioned that communal water was somewhere in the road near the house.
All in all we only paid for 3 water tests and the water filter. If you are renting out this house, your renters might want to see a recent test report.
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Check out how the sewage is in that street and if they have septics or closed tanks, check if they can't leak into your well. My old neighbours used to have a very leaky septic. Luckily they lived downhill from my house. Or just consider a form for filter immediately.