Help with training Prayer/Herb

I'm 71 prayer and would like 95, but how much would it cost and using what method? I know guilded alter but will infernal ashes be cheaper with that release?

And herb, I'm not sure what I want but I'm only 61 and would like a high level to make some extremes or whatever, I'd just like to know how much it has cost all of you to get 90's or so in it.

 

If you're serious and have the cash, like said above - Buy the supplies NOW, everything is going up - D bones included, because of the lack of botters / chinese people farming there now.