Downtown DC's latest big investment sale isn't in the East End, or even CBD. Rather, Dupont Circle has a major deal that could close soon. Multiple sources tell us Blackstone's 11 Dupont Circle is close to trading, with a price tag of $88.5M for the 155k SF office building. A buyer has not been confirmed, but we're told First Potomac could be the one—when reached for comment this morning, the REIT denied the rumors. Carr Properties has been mentioned as another suitor. If you're scratching your head about Dupont as an investment hotspot, think again: this year, Harbor Group International paid $1,600/SF for the Starbucks building on Connecticut Ave, and PNC is entertaining offers for the mixed-use property it owns adjacent to the Dupont Circle North Metro entrance. (Our theory: investors are clamoring for property near Bisnow's 19th and M HQ.)