How much would it cost to get 99 prayer in runescape?

Answer 1

That depends a lot on the method used, and on the current prices of bones, but in general you might expect a few hundred million coins, perhaps 200-300 million, depending on the type of bone used. For non-members, it is exceedingly slow, better don't even try it. Members can get faster prayer experience because (1) they can use better bones (and special ashes), and (2) they get 3.5 times the normal experience per bone (or special ash) if they offer it at a gilded altar (with both burners lighted).