What can be used as a proof of residence when applying a permeant residency?

[Hattymay15]

I am applying for a permeant residency and my father is my sponsor.
I was wondering.....
What documents could be used as Proof of Residence for him?
What documents my dad could use as Proof of employment? He owns his own business so I am not sure what I could use?
When it asks for all previous addresses, how far back do I have to date them? 5, 10, 20 years ago?
Any help is greatly appreciated
Thank You
Hatty