What does a mortgage broker cost me?
For most residential lending, nothing directly. Brokers are usually paid a commission by the lender that settles the loan. Ask up front whether any fee applies to you, and ask who pays them, because it is the question that tells you the most.
Broker or go straight to my bank?
Your bank can only offer its own products and its own credit rules. A broker can take the same application to several lenders, which matters most when the application is not straightforward, such as self-employed income or a lower deposit.
How much deposit do I need?
Commonly 20% for an owner-occupied purchase, though lower deposit lending exists and First Home loans have their own rules. It depends enough on your situation and the lender that it is worth asking rather than assuming.
Will applying hurt my credit score?
Repeated formal applications across several lenders can leave marks. That is a practical argument for a broker, who assesses which lenders realistically fit before anything formal is lodged.