H wrote:

Can someone tell me a reasonable price per 4x8 sheet for drywall
installation in Northern Virginia?

I just had an 11 x 19 room completely drywalled in Texas. It was bare
studs when they came in, and completely finished and textured when they
left. They did all four walls plus the ceiling. There were windows in
all four walls, plus the door, plus electrical outlets in every wall,
and an attic entry in the ceiling. Just under 700 square feet total.
Total cost $1575.