How often do buyers actually ask you for investment figures?

I started looking into the UK property market about six months ago and I've got a question for the agents here.

When an investor buyer comes to you, how specific are they? Is it "I've got £500k and I need it to bring in £2,500 a month" or is it usually much vaguer than that and the numbers only get worked out later?

And roughly what share of your buyers are investors at all, versus people buying somewhere to live in themselves?

Would you like to work more with investors or with ordinary buyers?