One audacious flipper made headlines after listing a newly delivered Rivian R2 in Colorado with a steep markup even though buyers can get the same SUV for much less. According to Electrek, a private owner in Littleton offered a 2027 R2 Performance for $79,900, which is $20,415 above its sticker price. What's happening? Posted July 1, the ad appeared not long after Rivian began delivering the R2 to its first customers June 9. It's a Half Moon Gra…