All single (yes you freshman… joking!) are required to live in approved housing, whether on- or off-campus. This is to give all students the further opportunity to adhere to the Honor Code. There are several off-campus housing locations available, simply do a Google search for them or go to the BYU Off-Campus page.
As for on-campus [...]

As an unmarried student at BYU, you are always required to live in campus-approved housing, whether on- or off-campus. Once you are a married student, you can live anywhere you darn well please, but you’ll probably be a poor married couple anyways so have fun!
You can search for BYU-Approved housing on their site, [...]

Concerning the three on-campus dorms, it is generally accepted that some are better than others living condition wise, but of course there is always the healthy rivalry between who is the best!
Those who have lived in the on-campus dorms often report that the best place to live is in Heritage Halls, followed by Helaman, and [...]

Help Required! I need more information, please click the Contribute link at the bottom to help out! Pictures of clean dorms would also be awesome!
As far as I have heard, here’s the lowdown. Deseret Towers is cheap, older, but fun to stay in. The rooms are probably 7′ x 12′, have two (hard) beds, desks, [...]

The date changes every year. For the 2005-06 housing year (if you are graduating in 05), the first day for applications is November 6th. Make sure you find out specifically what date it is when you come around to applying. The specific date is usually made available a couple months in advance at http://www.byu.edu/housing/.
The more [...]

Yes you can. You do so by entering in your desired roommate’s Social Security number during registration.

This all depends, of course, on where you live. On campus, you can choose from Deseret Towers (DT), Helaman Halls, or Heritage Halls. For the most accurate and recent rates for these locations, visit the Housing Department’s Rates page. For quick reference, peruse the following table:

Location

Room Only

Room and Meal Plan

Deseret Towers
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$5200 (Avg.) [...]