Stirling City Council has kindly offered the following comments (in blue) relating to garage sales.
 
(If there is no blue answer on a particular question, then a comment wasn't made.)
 

• Are permits required?
• Are there any laws controlling the posting of garage sale signs?
• Are there limits to how many garage sales one person can hold per year? No. But council advises that this activity must remain incidental to the residence and the sale must be contained within the property lot boundaries. Items / goods must not be bought by the garage sale holder with the intention to on-sell those items at the garage sale.
• Are there laws about using the footpath in front of the person's house? The sale must be contained within the property lot boundaries.
• Other comments offered.
• Is there a page on the web site that covers the laws relating to garage sales?

Disclaimer:
1) Laws are always subject to change.
2) If there is any doubt, you need to confirm current council laws.
3) egaragesales.com.au provides this information in good faith, but will not be held liable or responsible for any losses or penalties incurred as a result of changes to, or misinterpretation of, current council laws as amended from time to time.