Buying a runescape account online is a very risky thing to do for many reasons. Jagex the created of Runescape has had a policy out for a while which bans accounts sold and bought on ebay. You pay £100 for a level 98 account, your very pleased, you recieve the account and then you get a message saying the account has been banned.
How can they tell i hear you ask? Jagex have recently updated their software so they type in all the levels of the account listed on ebay and they come up with names of the characters who have that level. Also using the Xp on the level they can narrow it down and ban the account if they belive this rule has been broken.
As it says on the website, Jagex staff do know all the major auction sites and will take action against anyone selling their accounts. Their reasons behind this is that the accounts are often stolen. You buy the account only to have the owner recover it with recovry questions and you remain out of pocket and angry. Also that accounts remain the property of Jagex at all times and so you dont have the right to sell them.
I hope this Guide was helpful and will stop anyone resulting with being out of pocket.