Newbie to IT Contracts

I have given up my perm job & got myself a rolling 6 month I.T.
contract via an agency. I was given the option to either work under an
umbrella company or set up my own limited company. I decided to set up
my own limited company as this seemed to be the most beneficial method
of increasing my salary & not paying my new pay increase in tax, etc.
I have been advised to set myself up as a director, my girlfriend as
the company secutary, & then myself again as an employee, of which I
would then pay myself a minimal wage, then as my home is my registered
office, I can claim expenses for heating, etc from the limited account.
I have several questions though, I have read about IR35, if i can
prove that i do not solely work for one employee would i be outside of
IR35? I know as an employee I will have to pay PAYE, but who does
corporation tax work? Also, my main concern is that if i am paying
myself a small wage out of the business account (just enough to live),
but this would then leave monies in the business account, but say i
wanted to treat myself & buy a jetbike or something, can i use the
monies on the business account? How does this work, justification for
withdrawing out this money? would this then be taxed on top of my
monthly wage. Its all so confusing.

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