The timig of taking a contract

Which is better for taking a contract mortgage loan right now or 10 years later?
I think it depends on the term of your repaying mortgage loan.
Generally, the mortgage loan for the foreingers who do not have a permanent residency is high.
If you reduce the amount of having a mortgage loan, the total amount of repaying will be reduced very much.
And if you acquire the permanent residency after 10 years, the rate of mortgage loan you can take a contract will be reduced very much.

I think purchasing 10 year later will be better in alomost cases.