You can travel to and from Australia as many times as you want for 5 years from the date visa is granted. This is as long as the travel facility on this visa remains valid.
If you want to travel after the initial 5-year travel facility:
To see when your travel facility ends, use VEVO.
If you apply for the subclass 103 visa as a retiree you don’t have to:
This is a permanent visa. It lets you stay in Australia indefinitely. For citizenship purposes, your permanent residence starts on the day we grant the visa.
You can include members of the family unit in your application when you apply.  You are required to include details of all your family members in your application form whether they are migrating or not. Family members who apply for the visa must meet health and character requirements. Family members who are not coming to Australia might also have to meet our health and character requirements.
If you apply for this visa as a retiree, you:
Find out what to do if your child is born after you apply.