I didn't use a Forester, but I was VERY involved with mine, knew what I wanted and knew my trees AND used a logger that I had a lot of confidence in (actually distant relation). A Forester is a better way to go many times to ensure you get the best price and are using a logger with a decent reputation and the like. Logging is an ugly business.....but if done correctly can have a wonderful impact on your woods....especially from a habitat perspective.
I have logged twice and hired an independent forester on both occasions to walk the woods, mark all the trees we wanted to sell and then put it out for bids with several loggers to get the best price possible. They also inspected the loggers work and made sure they didn't tear the place up badly, cut trees they shouldn't, etc. Fee was very reasonable.
My first experience with logging, I got a mailer from Pike Lumber saying to call them if interested in selling timber, so I did just that. They came out and shot me a price and I was surprised at how low it was. Didn't feel right, so after talking to some friends, got the forester involved as mentioned above and tripled Pikes offer with another logger.
You can mark the trees, ID and measure them yourself IF you have the means to do so (may save you a little money with the Forester). Marking just requires a case of spray paint or more, and you simply create a list of which number is which species and the size (board feet per) on a log sheet. You can get bids yourself as well....depending on if you know/trust folks in your general area. if you have any specific things you want done/need done you need to have those listed as well. Trails fixed/leveled, culverts installed and gravel if needed even plot clearing can all be part of it if you want....just remember that they don't do it for free.