I live in a home right now that has no city water. It does however and city gas and electric. I live in a coastal mountain region where we have a well. I can't quite remember the particulars but I want to say that it is really deep, like 1500 feet down and the water tastes like spring water, but very hard. Obviously, the deeper the well, the cleaner the water as the soils and earth act as filters to cleanse it.
I will check the particulars when I'm at home but I think it produces in excess of 25 gpm which is plenty. There are homes with wells that exist with only 5gpm's. Your requirements are really dictated by how many people live in the home and what the usage will be. In my case, a 4 bedroom, 5 bath home, plus lots of landscape that requires irrigation.
We are required by the city to have a 10,000 gallon storage tank which supplies a fire hydrant in front of the house. So really, no difference than living in an area with city utilities, you would never know the difference. In addition, we are on our own septic so no city sewer either. Because the well pump works on electricity, I have installed a whole house generator just in case of a power outage. (we learned the hard way about a month after we moved into the home and lost power for 5 days. When that happened we lost the well. Not fun and never again, the generator was installed the following month) and I have been waiting for the power to go out since but it hasn't happened in well over a year
. So, the home is totally self sufficient.
I would think that when you make an offer on a piece of land and during your due dillegence period, it would be very easy to contact a local well company with knowledge of the water tables in the area. In your area where you get plenty of annual rain fall each year, I would think that finding water just about everywhere would be no big deal. Then just make sure that you have a water sample analyized for containmenants and E.Coli. Providing everythings clean you are home free!
As far as trucking water in...........there are a few people in my area that do just that. It is fairly reasonable but I sure wouldn't want the hassles.