One of my summer jobs when I was in HS was working on a drill rig doing water wells. I'm not in the profession, but I'm pretty familiar with it. The cost for putting in a well went through the roof (like everything else) the past couple of years. Cost will be primarily dependent on 2 things: How deep is the water table, and what type of casing are you going to use.

In Missouri, it's pretty common not to case the entire well. Most wells have the top 30-50 feet cased, and then the bottom 75 feet or so cased, with the middle of the well uncased. We went that route for well #2, and it was a mistake. There was a change in the water table somewhere in the middle section of the well. Water started coming into the uncased middle part of the well and waterfalling down the well. This churned up the water, and we started getting brown water coming out of the well. After a few months, the well collapsed entirely.

The most recent well we put in is cased in steel the entire depth. It was very pricey to put in, but it'll last (hopefully).

Drilling is about $20-25 per foot here now. 20 years ago when we did well #1, it was about $8 a foot for the drilling. Then it was around $12 a foot when we did the second well. Now it's doubled to about $25. On top of that you have to pay for the casing. You can use PVC, which is cheaper that steel to save some cost if your ground is stable enough to use PVC in. Then there's the cost of the pump, pipe or tubing from the pump, and getting electrical to the well and down the hole to the pump. Copper is expensive now too, so all those little things cost more than you expect.

Here in Missouri where the water table is fairly shallow, I wouldn't be surprised for a well to cost $12k to $15K to put in. If your water table is a lot deeper, then it's going to be that much more expensive.