Well......... you are right about most of that..... However:
Most of the time my fee comes from commissions paid by the vendors that I use. The cost of a travel advisor is already figured into the price they advertise, so there is no added cost. There are times however when I will charge a "package fee" if you are booking a totally customized trip (this happens very seldom). I don't sell tickets, which means that I don't just sell plane tickets (no commission as a rule).
You are right most of the time. If you want to spend hours doing all the research for hotels, transportation, activities you can then do all the booking for your self. What I bring to the equation is the experience of probably having been to the location, contacts at all levels of the trip, knowledge of discounts, special promotions, ability to handle everything with just one visit. I like to start with a face-to-face meeting with new customers, so we can get to know each other. I am a mobile advisor (no brick and mortar to hunt down) and will travel to a location that is convenient to you. Ideally, the entire group of travelers can meet together so all needs are met.
I'm sure you do know a lot about where you want to go. You have probably have done some research already to determine that you want to go there in the first place. I will try to fill the gaps of what you might be missing. I have had extensive training on a whole host of destinations and have traveled to all the areas that specialize in (Great Britain, Western Europe, Caribbean, Mexico, Hawaii, Alaska).
If you have questions, you can always call and ask me. I'm only a call or email away. Can't hurt to ask!