We're planning on between $2,000 and $2,500 (food, gas, accommodations, maintenance - barring any major catastrophes). Our plan is to go total hobo style, as much free camping as possible, oatmeal, bagels, pepperoni and cheese... and some beers! Shipping tires, filters, etc. to a buddy in CO (not included in our budget).
30 days, VT - WA via TAT, return via roads (something like Route 2 or less) about 8,500 miles
"Now that he had seen the hall he could no longer be satisfied with room 215. It was not enough. He longed to see the rest of the world."
(Beverly Cleary, The Mouse and the Motorcycle)