See prior post for profile evaluation. As to your questions....
1. Many top schools (i.e. Harvard) say deferred admission is considered on a case by case basis. Would my startup succeeding be a strong case for deferral?
Tough to say, as it IS so individual as schools indicate. You could always ask the question generally now if truly desired. But most likely if you are already working, it is a little tough to make that case.
2. Up until what approximate date would I be able to put in a request for deferral with a decent possibility of it being granted?
Probably a question to ask the admissions committee. Or hold off for now.
3. What top MBA programs allow you to defer your admission?
Likely case-by-case basis for specific circumstances.
4. If accepted to an MBA program, what will be my appx. decision deadline on whether or not to attend?
School will provide. Generally there would be a certain tuition deposit required, and you'd lose that after a specific date if didn't attend.
5. At what point does your age start making it less likely you'd be admitted to a top MBA program?
Tough to say exactly as there are often people at either end of the age spectrum in many classes. You can view the age range and often distribution in the Class Profiles on all schools websites to give you a better feel for specific schools. Often but not always, European schools have a slightly higher average age than US. Early to mid 30's and above is less common, in general.
6. What schools will waive application fees for low-income prospective students?
Many schools; check with admissions committees.
7. What schools offer the possibility of full-tuition scholarship/fellowship?
Most schools, but the number offered is often low-- meaning you really need to be an outstanding candidate. Also the earlier you apply the better.
8. How much will I hurt my chances of being accepted to a top MBA program if I take the next two years off to backpack the world? (My profile is provided below)
Two years would likely sound long to an admissions committee. Even one year or less could be a challenge. If you had a specific aim (like a community service trip or project for example), that could be slightly different. But generally you want to show that your career path makes sense, both before and after the MBA.
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