If a reservist is activated to a stateside position....?

The majority are considered unaccompanied as they are ususally listed as deployments, not a normal ignment/PCS. Chances are he will be given either a dorm room or a hotel room (which is still considered living on base). Spouses and families are generally not eligable or allowed to move, although you may do so if you decide to but will have to pay all the costs (rent included) out of pocket.