I don't bother with these. I did when i started in 2002, but dropped them after a few months. They were charging £20 a night and there were 3 others in there, one of which was a cheepy with small print. All people used to do is phone all of them, and usually if you were called first and gave a price, then they would get another straight after, and when told that their price was higher than mine, they would do a character assination on me and do the job for the same price.
Also, when they bring out suppliments, they will contact you to advertise in here as well. With leaflets, you are inspiring people to have their carpets cleaned, whereas people who only want their carpets cleaned there and then look in the paper. Todays paper is tomorrows chip wrapper etc.
Another point is: If you advertise Mon, Wed and Fri, and somebody looks in there on a tuesday, someone else will get the job. Also it is a fact that when people glance through publications, their eyes are always drawn to the right hand pages, whereas some newspapers print their tradesmans adverts on the left. This is a proven fact. Try asking for an advert on a righthand page when going in yellow pages and see what they tell you.
Dave
