Often a basic variable (cheap rate, no fees, no catches) is best for a small to medium sized owner occupied loan.  But if rate increases could affect your ability to repay the loan, then a portion fixed is like paying insurance.  Most investors are better suited to a professional package which although has an annual fee, has other benefits such as offset account facility and further ‘aggregate discounts’ where the more you borrow, the better the interest rate the lender offers.