Lending

When you lend money you want to know will the person pay it back.

You have to assume things during this process. What is it ok to assume?

Is it ok to assume there current salary will continue?
Is it ok to assume house prices will rise?
Is it ok to take into account illegal earning?
Is it ok to take thier word for it?

Fundimentally I think that as with life you should start with principles. What are your Principles? Then follows process and action.