We are currently building our home and want to make sure we get it all wired properly. If I want sound in various rooms, would it be reasonable to only put 1 speaker in the rooms, or will this not work, or sound right? Such as a bedroom or study.

The size of your rooms you want speakers in should determine how many you prewire for. Most speakers are mono, designed to work in pairs for stereo or in multiples for surround sound. There are single speakers that have dual voice coils meant to be used as a stereo speaker. They will require 2 sets of speaker wire ran to the speaker. I would recommend that in larger rooms, like bedrooms, office, or kitchen, that you should prewire the home for a pair of speakers to be used in stereo. It will provide the best sound. Be careful to consider furniture placement as well as in ceiling obstructions when doing the prewire. (I.e. Don't prewire your master bedroom with one speaker above the head of the bed and another at the foot. Like wise, don't prewire where your HVAC, plumbing, or even roof rafters will limit what kind of speaker, if any, can be installed in the ceiling). In the bathrooms I would wire for a single stereo speaker. 2 speakers tend to play against each other in small spaces and muddle the sound. Music is recorded in stereo (or better) so you shouldn't ever think of prewiring for less than stereo.