Currently my well only feeds my house, which contains the pressure switch and tank. The well is about 300-400 feet away from the house. I need to hook up some water troughs and an outbuilding whose water supplies run straight to the well. I'm thinking that it would be best to put the pressure switch and tank right next to the well. Is this the proper way to handle such a situation or am I missing something important? Also, would it be wise to have a pressure tank in the house and outbuilding as well (three tanks total) to get good pressure at each building, or is this unnecessary? Thank you.
There's no need to change the pressure switch location, if it's already installed and working where it is.
You can add pressure tanks near the various points of use if you feel the need, and they will work without any other change to the system. In many cases you won't need them, or they will be far too much hassle to install with respect to keeping them from freezing in winter - (Don't know where you are at, your screen name hints at Canada, where I'm at it's a problem and you ether need a heated space or a deeply buried vault to put a tank in.)
Edit: If you have a check valve at the entrance to the house you would have to remove that, or move the pressure tank to be before it. After considerable research I have only the check valve at the submersible pump.
only if you have a line that 400 feet away from your tank that is 1/4 of a inch. you will have two problems. one is that you use to much water for your pump to keep up with. second at a give presser your flow rate will be maxed out due to the size pipe you have. so if you have a 1/4 size pipe. you wont have any flow. because it will take alone time for water to flow. now if you really want some flow. put a 12 inch pipe to your buildings. still just having the one tank. but to be real for a second, just install a 1 inch line to the buildings. unless you have a 5 inch spout the one inch line will do you fine. to answer your question if your tank stays at the pressure 80 pounds. your only reason of no flow would be the pipe size. you want more flow. get a bigger pipe