Hi All,
I feel like I'll be much more qualified to figure all this out post MBA

, so I'd love for someone to take a look. Hopefully it will help others as well. This math may be completely wrong, I'm an engineer not a financial analyst!
Let's say for the sake of simplicity that the total amount I'm borrowing over 2 years is $140,000, and I'll look at CommonBond fixed rate only. What I want to determine is the trade-off between full deferment, and making interest only payments while in school.
Terms are all the same:
- 6% APR fixed
- 2% fee
- 10yr period
For simplicity, let's break it up into two equal loans of $70,000 (this is how it works right??).
Year 1
- Loan amount: $70,000
- Deferral period: 2 years
- Principal after 2 years: $78,924
- Monthly interest accrued: $371
Year 2
- Loan amount: $70,000
- Deferral period: 1 year
- Principal after 1 year: $74,328
- Monthly interest accrued: $360
So with no interest only payments:
Total principal after deferral: $153,252
Monthly payment: $1,735
But then it looks like in year 2 I'm accruing over $700 per month in interest. Let's say I pay that down every month, and my total principal upon graduation is an even $140,000. My monthly payment only goes down to: $1,585. Only a difference of $150.
I'd rather pay an extra $150/mo once I have a job than $700 per month with no job. It seems as though interest only payments are not worth it.
Is my math wrong / should I have come to a different conclusion?