In the event of the theft of your vehicle you will be required to file a report with the company, as well as with the ministerio publico (a police report). Upon reporting the loss, you will be required to provide paperwork to the company in order for them to process the payment. You will be indemnified the market value of the vehicle minus the theft deductible. The market value of the vehicle will usually be calculated as the Kelly Blue Book private party value.
In the event of a total loss, MexVisit can provide plane tickets home if purchased. One thing you will be asked to do, as a part of the process is to cancel the vehicle importation permit. This can be difficult, especially if you are far from the border, as it is typically best to cancel the permit at the same entrance where it was obtained. If you have MexVisit they will actually process the cancellation for you.