I have an idea that I have already applied for a patent but I don't know enough about cell phone technology to make this work. My idea is a cell phone, yard sale ap. People download the free ap to their phone all over the USA. People that have a yard sale can click the ap to notify everyone in their area about the yard sale. All the phones in 10 miles receive the signal to tell yard sale folks about this yard sale. No need for yard sale signs on every street corner. The person that has the yard sale pays 50 cents to use the service. With all the millions of yard sales each weekend if 10K people use the ap that = $5k every week. How do you make a phone ap for yard sales? This can also be used for estate sales and auctions.