Best Way To Treat/Filter Campground Well Water???

Being a seasonal and you'll be using it a lot ask whoever what type of well. We had spot and state classified that water had to be tested twice a year. Tested by independent water testing place. Turned out water was great but only 8 miles away had high arsenic levels that requirement filtering. Think it was $70. So all depends on what you need filtering for.
You won't know for sure till you get it tested.