I'll let you do the math as to whether you can make a living at it or not.
Yep, there are exceptions to every rule. I'm basing my opinion on experience in management with one of the big supplemental companies (I can give you a good idea of many people they burn through) and on people I've known in the business. My experience is that less than 10% (and possibly less than 3-5%) make a decent living (let's say $75K plus) doing only supplemental.
Agreed, though, That doesn't mean it can't be done, but there are other options.
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