There are a lot of pristine SeaBirds for sale because they won't take off and then crash properly-putting themselves out of your misery.
They just taxi around at what should be takeoff speed. 
They were among the first ARFs...When they scream by on the surface at 40 mph, they really look Almost Ready to Fly!

Guys tend to strip out the engine and radio gear, and throw them into the attic for 10 or 15 years.  Then they are rediscovered and offered for sale to unsuspecting newbies. 
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