thanks for the comments. Regarding the guest posts, I do post them at no charge. I figured that it is mutually beneficial because it saves me from having to write the article myself and it helps them spread the message that is important to the writer. Normally, I allow the author to add a link or two but if it is an exceptionally well written article I will allow a few more links. Although I have never charged an author, I think that the option should be available to me if I needed another source of income in the future. My site is very big. Why shouldn't I be able to charge some one to post something. It is like a huge TV network charging for placing a car commercial. The car company pays the network because having an ad on TV is an important location. My site is important to the fashion industry, so it should be fair that a clothing company pay me to use my online real estate to promote their message. OK, I get the fact that on TV we know when they are having commercials. However, let's keep in mind Coke, Laundry detergent, and other items are often held by actors in TV shows and movies. Doesn't the show some times get paid for product placement in the show or movie???
On around 99.9% of my pages, I have a link to "legal notice", which includes comments that indicate that I use advertisements on my site.
Regarding unpaid directory, I do charge for listings, but I also create listings for free sometimes. My directory is not an automated process. I create each listing manually so I feel I deserve payment.