With floor-to-ceiling windows, in-wall speakers, and built-in bookshelves, this 12th story Penn Quarter condo is on the market for $724,900. The majority of the guesses for this week's PriceSpotter were right on the money, hovering around $680,000 to $749,500. A commenter named RFC guessed a whopping $1,090,000, which is thankfully not the actual asking price for this listing. Phew! Washington, D.C. house prices aren't that pricey (yet).