Press coverage can be very valuable to a start-up as it can lend credibility and help build trust in a brand. I am sure you have seen many web sites touting "As Seen In" followed by a list of media logos. Press coverage can also help tell your story in ways that advertising can't.

You may want to consider finding a PR consultant that specializes in your specific industry. They may consider working on a project basis unlike an agency that will likely want a monthly retainer.

Either way, I highly recommend developing a very clear set of objectives and managing the PR firm/consultant closely. Never set it and forget it!

Let me know if I can help you to further define a PR strategy and select the right PR consultant for you.