Once you get orders to your new assignment, you'll be able to get in contact with the Housing Officer for that area. They will be able to tell you what your housing options are. Small boat stations will not have housing available. You'll live in the community, using your housing allowance to cover your rent, etc. Larger bases may or may not have unaccompanied housing. Base San Pedro (Los Angeles area) does not have housing of any kind on base. Married personnel can get housing at Fort MacArthur or Naval Weapons Station Seal Beach. Single personnel will live in the community, as I previously mentioned. Base Alameda (San Francisco Bay area) does have housing for single and married personnel. All this to say there's no hard and fast rule. As I mentioned before, the Housing Officer will be the best source of info.
As a side note, you're posting in the CG Officer subforum. This is specifically for officer commissioning program info. A lot of your stuff should probably go in the General Questions subforum, unless you're looking for rating specific or boot camp specific info. Then post in those subfourms