May I know reasons why are you selling it for only 20$? Is not it worth a bit more? I hope you are not trying to sell it and then report the theft...
Could you or somebody else tell me how steam account recovery works? If I purchase this for $20, what methods does OP have of recovering his account back?
Well if Op did sell you the account and reported it hijacked then steam support would almost certainly side with them as they would have the same IP, Credit card that is registered to the account and control of the email address that was used to register the account. It is also fairly suspicious that OP wishes to get rid of the account for only $20 as i would value it around at least $50 and that leads me to believe that OP may have hacked someone else's account and wishes to dump it on someone else before they recover it.