Standard prices are the official Grand Exchange guide prices. I will include a beginner EXP rate and a click-perfect EXP rate for every method The price depending on the butler (regular or demon) and the method used. The cheapest way to 99 construction will cost you around 130-160M to get from level 1 - 99.
The occult altar can be built in the altar space of the achievement gallery in a player-owned house.It requires 90 Construction to build and when built, it gives 3,445 experience.The player must have a hammer and a saw in their inventory to build it.Home Altar osrs Construction Occult altar - OSRS Wik