I just finished a Facebook live session, where I talked about the pros and cons of hot dog carts vs. food trucks. Which is better for you? The short answer is, it depends on what you are doing. Open carts are more affordable and easier to maneuver than trucks/trailers, but have more menu limitations. With a full enclosed truck/trailer, you have more menu options, but you will still need a commissary, it can be harder to find a location, and it's much more expensive than a cart.
For more details, watch the video. Don't forget to check out StreetFoodPro for tons of pro tips and vendor discount deals!