Well water maximum issues

We’ve talked a lot about wells, and of course city water is better to have in the event of issues, but I am trying to get my arms around likely max exposure in the case of having a well. I am taking a look at a 30 site park that has a well (city sewer at least), and am trying to attach a maximum dollar in the event of a worst case scenario. I would not anticipate any issues short term by having proper inspections prior, etc., but want to be prepared. I would love to hear feedback on well experiences in general.