Tbh an account that is a little unique so say a 10hp with something like 99 attack or hp a lvl 3 with 99 slayer people like things others ain't got so they can get more attention off people when playing. Those are the accounts people tend to purchase. But imo i just prefer a simple main account i can do anything i like on. Each to there own.
They like 99's. If you make an account with 99 fletching, firemaking, strength, and cooking,(with 15m) you can sell it for $115 easily. That's about 1.5 months work.