ILR Maintainance

[mah]

Dear All,

I am going for my ILR in next few months.

My question is regarding income and finance in form SET (O) section 5 questions 5.1 to 5.3.

5.1 my house is pivately owned
5.2 do you or your partner pay rent? Yes
how much each month? for example £1400
5.3 Are you working? Yes
How much you get after tax? for example £1750
(How should you calculate this if in addition to full time employment you get money from part time employment and self employment as well, because they may not be routine income)
(What happens if you are unemployed in the time of application, for example got redundant just a month before)
And my other question is, can they refuse your visa as your monthly income is less than your monthly expenses (For example you use from savings and/or you have got loan from the bank and use that one for a while)

As I know the ILR doesn't need any specific amount to show as maintainance fund. But why they ask documents on page 44?