why only pay $636 for 30W homeloan, interest only?

ylruan

I have one investment property, and homeloan was 32w three years ago, and pay $2100/month for principle and interest. Now I plan to transfer to NAB, the homelaon manager told me I only need to pay $636 one month for interest only. The interest rate is 6.77% for 1M homeloan(still have other potentail property). I suspect this number, much different from what I got from internet.

Can you please compare this to yours? Is it approxiamtely right or not? Many thanks.

The total payments for all the properties determine if I buy the house which will increase my homeloan to 1m.