It's realy all part of the same thing. In the ferst few minutes you'll be able to tell if they want to listen or not. Some people are happy to get a tree phys 101 lecture, while a few just want a number. tehn you take your boiler-plate breif statements as to why you do what you do.
If you have a script that you can easily adlib to then you wont sound all "um ahh err yaknow", practice it on the help, the kids, the wife, and the dog. I know the gist of what I said to Mrs smith about here Norway maple 6 months ago because I use the same general statements most of the time and the same thing goes for detailed notes on the bids. Boilerplate language that you can write while doing something else, or have in your computer to cut and paste.
But I digress, al;l customers are different, but you can gorup them together and treat different types accordingly without being dishonest, it's just part of the service.
Just watch out for the lonely old ladies that just want someone to talk to but cannot afford the work. The thing to do here is find something small you can do for them for a little cash to cover your trip, 15-20 min pick-pruning the front phitzer as you talk.