I am on yell.com with a paid box and have had one job from it. The turnover from the job just about pays for the ad. If you calculate the proifit from the job, it is less than the cost of the ad. The YP man has been trying to get a meeting with me for a few days. I've not been intentionally avoiding him but we haven't been able to cross paths yet. I do still want a paid ad in YP but I will be reducing it to a three line box. I am stuck with the ad on yell.com for some months yet. I haven't decided where to go with that. Typically, I had made up my mind to just have a one line freebie in YP when I got a decent job from it that cast doubt in my mind. I got no more work from a larger box than from a three line box.
One problem with YP is that you get no say in where the ad is positioned on the page. If it's at the bottom of a column or, more poignantly, by a page fold, it does get viewed a lot less. At least with yell.com you know that if you pay for a box you will be in the rotation of paid ads at the top of the page. You can also edit the ads periodically to try different things out. Mind you, I think it's a brass necked cheek expecting someone to pay about an extra £160 - £180 a year just to be able to insert their email address and weblink on there. I didn't realise that when I signed up. I can't recall if I was blatantly lied to or if the info was suppressed.
The BIG drawback to this type of advertising though is that YOU CAN'T TARGET YOUR IDEAL CUSTOMERS . I seem to get a fair few people wanting one off end of tenacy window cleans. Why oh why do they always leave it until a couple of days before they vacate? If it's local and I can do it first thing before leaving town for my regular work then OK. Unfortunately though, these types of jobs frequently seem to require specific appointment times that I can't manage.