Question: Nissan GTR R32 (Australia)?

Hey guys,
I am having a trouble with choosing the right R32. I’ll be getting my p plates soon and I thought that I should get an R32 now before it’s too late and their price value inreases. I see it as an investment not only as a toy.
My major question is, what is the price range should I be looking at? Does it depreciate the value of the car if I upgrade it with couple of mods (new spark plugs, coilovers, boost gauge, etc.)? Lastly, will the price be higher in the following years or is it at its peak now?