Ahhh, my bad. 400k, yeah, that'll take some time to get through all of that!
After just doing a well and septic this year on our cabin, I'd say those numbers are fairly accurate. The well simply depends on the depth. One thing you can do to get an idea on how deep your well might end up being is to go to the state website for wells and permits and search for that area. You should be able to figure out how deep the neighbor's wells are. Obviously, the depths can vary from spot to spot, but that should give you a good idea at least. Our well ended up being about $18k for 240'.
Our property is also pretty rocky, and we had to do a fairly large septic, but luckily didn't need to jackhammer any rocks. The final cost of that septic came out at $15k, so I'd say you might be a little high on that price, but obviously prices can vary in different areas too.
If you have any questions on this, feel free to PM me.