.... continue from previous post.
Correction: the installment on the 500k loan should be about 23k, not 22k.
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Cost of InterestBefore continuing how John will get the same total cost of interest, first, allow me to explain why cost of interest is important.
As most of us are salaried employee, whether highly-paid or otherwise, we can more or less extrapolate how much earnings one would made in his/her life - the X amount. How much of this X amount remain is dependent on how much is the expenditure.
If we view money matters as a game plan, then there is 'defensive moves' and 'attacking moves' in managing our money.
Defensive moves would be protecting the wealth we have generated; and it is mostly on ways of spending wisely. Simple logic: spend wisely, saved more ... more X amount remains.
Cost of interest is a cost and expenditure. So less spending on interest and 'defend the wealth' whenever possible.
So, if John incurred a specific amount of interest if he will to take the 1st loan option, we will based and concluded it whether or not it is a better 'defensive' move if he selected the 2nd option.
If the 1st option is the less costly than the 2nd option, then selecting the 2nd option is not a better defensive move.
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How would John get the same total cost of interest when he selected the 2nd option?The interest on a housing loan is calculated on the balance outstanding amount. So the maths logic is pretty straight forward.
1. The lesser loan amount and shorter tenure is less costly. So option A is less costly.
2. To have the same total cost of interest on the flexi loan of 500k, 35-year tenure as the 400k, 15-year tenure, John would have to emulate the amount of outstanding balance as in the 400k loan.
(Remember that interest is on monthly rest basis.)
The easiest way to have the same outstanding balance as in the 400k loan is:
a) put in 100k into the flexi loan, and reducing the 500k to 400k.
b) pay the same monthly installment (about 3k) as in the 400k, 15-year tenure.
c) pay the same monthly installment (about 3k), every month in the first 15 years.
Other variations of paying the various amount of installment, like less installment this month, and then more next month can give the same result. But above same monthly amount is the easiest steps to emulate.
As interest is on monthly rest basis, interest once it is incurred is already set.
Any lesser amount paid in the beginning of the loan, a much higher amount will be needed to reduce the monthly interest, such that the total cost of interest can be capped and be the same as in the 400k loan.
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The half-empty, half-full glass perspectiveSo, as explained above, to have the same cost of interest on both loans, John would have to do the same whether it is option A or option B.
But in option B, John has an extra 100k at his disposal. Is this good or bad, an advantage or disadvantage? It depends... how John views it.
Will it change his monthly spending? Will he be enticed to withdraw part of the 100k for another purpose?
It can be safely said that John will incurred more interest with option B... unless he will be very strict in his monthly budget and follow strictly to the 400k loan payment schedule.
You know, you post such long story to basically come to a conclusion that most of us already know..
Option b being the more flexible option allows john the freedom to match a fixed loan, allows john the freedom to pursue other investment opportunity if it comes up, allows John to react to emergencies if required, basically to do whatever he wants.. With the downside of temptation to waste money on other things and not discipline to stick to plan..
No offense, but it's not some huge discovery. Many other posters gave same answer without the tl;dr