Dose - Help figuring amount to try when switching opiates PLEASE!

[dannygyrl]

If someone was to switch over from oxycodone to H how could they figure out what amount to begin at? Hypotheticaly let's assume that the person in question takes 120mg orally of the oxy every dose and does this every 4 hours if handy. How would someone figure out how that would equal to a dose of H. Also would have to figure that the person is only being exposed to the black type of H in the area they reside. I would assume that financially this would save a person a lot of money to switch over since i'm guessing that each dose is a minimum of $80 sometimes up to $100.

Also put into the mix that the person would be using either by bumping, orally, smoking. I'm thinking probably a combination of bumping and smoking.

Thanks to everyone for their input in advance.