Talk to people who have been doing this for a while. Actually, any consultant that works this way won't be in business very long.
Consultants vary wide spectrums of skills and purpose.
And I don't know of any that start anywhere near this rate. What can your expertise bring to the client. Most consultants won't share the risk with a company. And for the most part this is the way it should be. But this is also with non-independent companies, where there is a support structure behind a set of individuals which provides added value and security.