Question of license requirements across states

While all states grant reciprocity for driving licenses, this reciprocity doesn't apply to anything else related to your coach. If your state doesn't require toad brakes but the state you are passing through does, you are violating their laws. If your state allows double towing and the state adjacent does not, you can be stopped and ticketed (more likely forced to disconnect). So you do have to pay attention to traffic laws that apply to your vehicle in the state you are in.