^^^ you really should consider flying to Vegas and either renting a car/SUV or a motorhome. Saves a TON of driving and you're going through Vegas anyway. Very cheap flights from Bellingham.
The route we have planned is 4900kms return. We're going to be driving down in my buddies Merc Sprinter van, towing my 16ft travel trailer. He says it will be 12L/100km (will see how that works out towing), budgeting for 600-700L of fuel. Based on a .90 exchange rate and current Moab gas price conversions, gas will be .97/L = $600 to $700 in fuel.
Accommodations are taken care of seeing we're towing the trailer. Depending on the RV park we stay at, $35 to $50 a night (for the resorts with hot tube, pool and laundry), for 5 nights = $250. Staying side-of-the-road or in the desert is free.
Gas and accommodations for 4 guys will be around $250 each. Food is what ever we make it be. Eat well or eat thrifty, we'll see what happens when we hit the road.
I did Interbike last year and the flight to Vegas return from Bellingham was $230 CDN. But there will be oversize luggage fees for the bikes. We'll need to pay for accommodations everywhere we go. Add on car or motor home rental and milage, things could start adding up quickly.
Yes, you have a point about flying. We would save a considerable amount of time. But isn't driving the pilgrimage to Moab part of the Moab experience? I think we would be cheating it and ourselves by flying down.