I bought a house outside DC. Unless I retire to the mountains, I'll grow old here. It's my second home, the other was a few miles away, I've been in this area since 2000. Pretty sure my middle-management position fits my squarely in "professional, upper-middle-class."
Most of my friends are similar. Moved here after college, no plans to leave the area, almost all are home owners, and upper-middle-class.
Is what I should say to you. I should not have to inquire the specifics of your personal life to figure out your true income, who has maybe subsidized your living expenses over the years, and your total expenses, to determine how you were able to save for property in one of the most expensive areas of the nation. Although, you have already earmarked your comment with "upper-middle-class", which speaks to your ancedote-rooted perspective.
That’s simply not true. Thousands of people buy homes suburban DC every year. And not all of the white collar buyers plan to move in 5 years.