The rental market fluctuates in Virginia. Due to war times, many more military families need homes to rent and or buy are in the area. Statewide vacancy rates run between 4-8%, depending on what branch of the military is called up for duty.
I think it is important for students to acknowledge that a PhD program is a big investment on their part, but that investment should go both ways. Make sure the school and program are willing to make an equal investment in you.