Who can't be a councillor?

Some people can't be a councillor because...

1. they work for the council they want to be a councillor for or work for another council in a politically restricted post
   
   
2. they are bankrupt or have been surcharged in excess of £2,000
   
   
3. they have served a prison sentence (including suspended sentences) of three months or more in the five years before the election
   
   
4. they have been disqualified under any legislation relating to corrupt or illegal practices