It is assumed that two burners are lit while using the gilded altar and does not include the cost of clean marrentill.
A player choosing to use reinforced dragon bones all the way from 1-99 Prayer, using a gilded altar with lit burners and no other experience boosts, would, if all the bones were bought at the current medium price on the Grand Exchange, spend 395,462,676.
Additionally the first bone would take them straight to level 7 Prayer.
Using the ectofuntus would cost 346,029,842, but would take far longer to do. Simply burying the bones would cost 1,384,119,368.
Cremating the bones would cost 553,647,747, and would additionally give 10,427,545 Firemaking experience.
Reinforced dragon bones were originally called rune dragon bones upon release, and their examine text was "Dragon bones infused with runite ore." This was changed into their current name with the 10 April2017 update.