I take it you're planning on getting yours detailed before our trip
I've only had my car detailed once - and it was at my dealership (Manhattan Motorcars) since their price was similar to the other so-called "detail shops" in the city. I had one experience with the West Side Highway detail shop. You would think that all they did was wash cars quickly and sloppily but they do have a detailer on site. I left it there for half a day, right before I took the car to the Hamptons. They did a fabulous job. I was impressed with how well they detailed both the interior and exterior.
If you can take a trip north to Westchester, I can recommend you excellent detail shops around me. Also, I'll detail your car, but for a fee.