A lot of us for one reason or another only have a car or SUV. In a bug out situation, this can be a problem. One possible solution can be to get a cargo trailer. But for people who live in apartments or other situations in which they can’t store a cargo trailer there is another possible solution.
Get a trailer hitch cargo rack or cargo box. They are a rack or box that has an extension on it that fits the receiver on your trailer hitch. This extends the length of your vehicle but permits you to carry more supplies.
These are available at numerous dealers on the internet and at most truck supplers. They are reasonably priced and are easy to store. If you get the box, you could keep it full of preps. I have also seen examples of boxes that have been custom made to fit the racks and some of these are made from diamond plate and quite secure.
Roof racks are an additional method of increasing the storage space in your vehicles. The two combined could increase your carrying capacity by quite a bit. Just be careful not to overload your vehicle to where it becomes a problem.