Ferguson makes the revelation in his autobiography.
Sir Alex said: ''I remember a local Manchester businessman coming to me and saying 'I'm thinking of buying Birmingham City, what do you think?'
''I said, 'If you've got a hundred million pounds to risk, go ahead.' 'No, no', he said, 'they're only eleven million in debt.'
'''But have you seen the stadium,' I replied. 'You'll need a new stadium, for maybe sixty million, and then forty million to get them into the Premier League.'''
He added: ''People try to apply to football the usual principles of business. But it's not a lathe, it's not a milling machine, it's a collection of human beings. That's the difference.''
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