MBA Scope

The mathematical answer to your question is quite straight forward to calculate. The median salary out of a Stanford MBA is $125K with an offer rate of 94%, so the expected salary at graduation is $116K. So you will spend $200K for a 1st year return of $116K. Then you can add other things, like expected growth, opportunity cost, some kind of value to intangibles and happiness. If you want you can even throw in some black swan events: If I go to Harvard and start a company with a classmate and an insane exit, I will make $X, but the time for that is Y (discount it over 7 years assuming it is VC funded) and the probability of it is Z (where Z 1% for sure). See Badreddin Edris' answer to Is it worth spending $200k for an MBA at Harvard? For a nice answer that looks at this issue from a qualitative perspective. On the other hand, the likely situation for an individual is a desire to leave what you are currently doing. This is the best reason to do an MBA, not the calculation I presented above. The reality is that it is easier to convince someone you can switch fields from school than it is once you've started working (though not impossible ofc). Also, by definition you will be surrounded by people who've done a variety of things and so you can learn from them to figure out what you want to do next.

Auditing is expressing opinion on true and fair view of state of affair of area under audit, reporting gap or finding and providing a recommendation, which management may decide to implement. Consulting start with problem for which solution has to be found, it is assisting the management for getting the problem/issue /area of consulting addressed. Auditing stakeholder can be both external and internal, consulting stakeholders are generally internal management. Both require different mindset of professional performing the task, auditor has to be person with high repute, technically sound and able to understand visible /invisible information, high on ethic and integrity, he should have courage and conviction, and report transparently. Consultant should be expert in his area of consulting, work like trusted advisory or friend who can understand the concern well and provide implementable solution both over short and long run. To answer your query, yes MBA would help you in becoming a successful management consultant.