After a long time of trying, I eventually got around to building my own gilded altar. It is relatively costly, but I have 24 more prayer levels to go and this should help repay the cost in the long term.
Unfortunately, I do not have dragon bones in stock to get up to level 99 prayer, so I know one of my future goals will involve a lot of dragon fighting to be able to stockpile some bones to use for raising my prayer skill.
I am currently level 123 combat and require another 23 prayer levels to obtain 126 combat. If I bought the bones, it would be quite expensive - so I am most likely going to mix some buying as well as gathering bones. This means it will be some time before I reach level 126 combat, but I am not in any major rush.
Overall, my player owned house on runescape is rather under developed - I have been concentrating on other things and not really trained construction skill up much (it is currently level 72 as I used a crystal saw to build the gilded altar).
I also purchased an addition 2 marble blocks - as had expected each burner to require two blocks. Instead, both burners were built and used only 2 blocks. The overall cost is still reasonably significant. The cheapest way to achieve the gilded altar would only be to build the actual altar and the burners.
Cheapest gilded altar cost:
- Gilded Altar = 1,170,000 (1170k) for 2 marble blocks and 4 gold leaves
- Marble Burners = 650,000 (650k) for 2 marble blocks