Did you want to know who pays a mortgage adviser?
In New Zealand most mortgage advisers get paid a commission by the banks for residential lending so they do not need to charge you a fee. For loans that are sourced through the non bank lenders there will typically be a broker service fee which is specified within a loan offer and often paid when the loan settles, but these fees are ultimately paid by you as the borrower.
The mortgage adviser will be able to explain how they get paid once they has done the initial assessment and know which bank or lender will be used.
There are some mortgage advisers that will charge an upfront fee, and others will commit you to a fee should you repay your mortgage within the first year or two years as they may have to repay their commission to the bank. Again, these fees should be disclosed before you commit to using that broker.