One of John Kevill's closest friends, Beau Higgins, was serving in Iraq 10 years ago when one of the Marines under his command, Travis Manion, was killed by a sniper in Fallujah.

Beau sent John a copy of the letter he delivered to Travis' family following his death, and as John sat in his K Street office reading it, he says it hit home how much some were sacrificing so the rest of us could live our normal lives.

Now John, a principal with Avison Young and its US capital markets managing director, is training to run the Marine Corps Marathon to support the Travis Manion Foundation and honor the legacy of Travis and his Naval Academy roommate Brendan Looney, a US Navy SEAL killed in Afghanistan. The two are buried side-by-side in Arlington Cemetery.

"Seeing firsthand how my close friend dealt with the loss of one of his Marines, and watching the Manion family react to this tragedy by creating a foundation to provide support for other Gold Star families, is both humbling and inspiring," John tells Bisnow.

John has already raised more than $30k for the foundation and hopes to reach his $100k goal by the Oct. 30 marathon. He says he welcomes any donations and no amount is too small.

"It's been amazing to see the reaction from the real estate community," John says. "Even if, like me, they haven’t been directly involved in the military, so many appreciate the sacrifices they make so we are able to do our deals, develop our communities and just be safer."