Washington D.C. to Seattle - April 9th until ???

Hi there! I'm flying into Dulles International Airport on April 9th. On April 10th I plan to start a cross-country trip from DC to Seattle - using only recycled bikes/parts. I'm wondering if there's anyone located near D.C. who could help me with logistics?

I want to get a decent used bike at a Goodwill store (or two and piece them together), then depart for the initial ride on the GAP/C&O shortly thereafter. I will be bringing 26" schwalbe tires with me. My Park Tools are safe and waiting for me near Pittsburgh, but I'll have enough tools with me to do what might need to be done in DC.

Or does anyone have an old bike they'd be willing to freecycle? My standover height is 30".

There are a ton of great bikes/parts out there with useful life left, and I plan to highlight that fact on this journey.

Thanks!

Nathan