No one buys Jr. Member as far as i have seen
Full member may go for around 0.07 to 0.1;
Hero member may go from 0.1 to 2 BTC
Legendary member may go for really higher prices (although I've never seen one on the selling category)
legendaries won't go for less than 2BTC. I think 2-5 btc or more.
I've seen some offers for them in such range, but don't know if someone really bought them