Since I am doing a Yenko clone, you can guess my opinion on clones. (if I had any influence in this hobby, I would change the name to "Tribute Car")
Some folks use the terms "clone" and "fake" interchangeably. In my opinion, the only difference between a clone and a fake is intent. If you make one car look like another, then it is a clone. (I suppose if you do this with respect for the original, then it is a "Tribute") If, on the other hand, you make one car look like another, and then try to pass it off as something it is not, then it is a fake.
Again, this is just my opinion, but lets say you take a 69 plane jane, drop in a 454 with a dominator intake and carb, and 700R4 tranny, install houndstooth interior, and weld wheels, and paint it viper red. Then you put on Yenko stripes, and call it a Yenko clone. IMO, that is not a Yenko clone, but rather a cool street rod, with Yenko stripes.
Said another way, Stripes to not a clone, make.
As for price, you know the drill about one man's trash is another man's treasure. Dave, you are entitled to laugh at the prices some clones are getting, but while you are laughing, someone is buying.
Turn that around, and look at the prices real Yenko/COPOs are bringing. Same thing goes here. The prices have risen so dramatically that they are out of reach for all but the most wealthy. Take a guy who bought his 10 years ago for $20-25 grand. He may decide to sell for $150, and he may be laughing (albiet, all the way to the bank) But the point is, in order to sell for $150, someone has to buy for $150.