The Municipal Code contains the rules governing yard sales (section 9.08), and yard sale signs (section 9.08.050). See the Municipal Code, Title 9 – Land Development and Public Improvements (PDF) for specific details.
You can hold a garage or yard sale twice a month - but no more than 6 times in a year. These sales can be up to 3 days in a row.
You must hold the sale on property you regularly occupy, unless it is a multi-family sale held on the property of one of the other participants.
You must keep the sale items on the property, they cannot spill out onto on streets, sidewalks, or other rights of way.
You can use 6 signs to advertise or direct customers to your sale. The signs cannot be larger than 3 square feet each.
You can place the signs up to 24 hours before the sale, but must remove them 1 hour after the sale ends.
You can put signs on other properties, if you get the permission of the property owner.
You can put up to two signs on city streets or sidewalks, but they must not create a hazard by being on the traveled part of the road, or in the pedestrian part of the sidewalk
Other prohibited sign locations:
If yard signs aren't removed within 1 hour of the end of the sale, or they're placed in any of the prohibited locations, you could be fined up to $250 per sign.