What dollar amount do you set for your time?

Over the past several months I have been approached by individuals to discuss things such as ways they can attract new customers, should they be advertising to questions about setting up blogs to market their own companies. I have been happy to meet with these people and share ideas and stories and brainstorm with them to find solutions. What has been the cost? While in most cases a drink, lunch or quick stop at Tim Hortons. In a few cases a barter relationship was set up, exchanging of service such as a landscaping project I needed completed or some free products. Hmmm, beer.

Last week I was asked to work with a client to develop a blog and help with a lunch of a new service they are looking to do. At the end of the meeting the simple yet hard to answer question was asked, "Before we meet again, can come up with a number you want to work with me on this on an hourly basis?"

How do I assign a monetary amount to what my thoughts are worth? Well you could always look at what your employer is paying you on an hourly basis as a starting point, but that does not reflect properly. An employer paying you a set wage has invested in you based on full time employment where as a consulting job is short term. Do you double, triple that number to come up with your consulting rate?

A few factors I have decided to work into the equation are:

Potential Revenue Generated by client
Size of clients current business
Level of stress/heavy lifting
Potential for repeat work

Does A + B = $, or do you take C x D = $, is their a secret formula I am missing? I will be thinking about this over the weekend, but welcome your ideas and thoughts.