Have at least 3000 gold by Part 4, Chapter 5. When you see Volke at the bottom-right of the screen, talk to him with Elincia or Bastian and you will recruit him.
You can't. You get Volke in Part 4.
You can't. There are no cheats in Fire Emblem Radiant Dawn.
No, Radiant Dawn is only for the Wii.
No she died in Fire Emblem Path of Radience
in a store...
Yes, there are.
Oliver
I think not.
It already has been.
About 20
No.
no
As of now, you cannot.