For many reasons I have had a dashcam installed in my vehicle for several years. Thankfully I’ve never “needed” any footage off of it but there are many times I was thankful to have it for peace of mind and entertainment value. They are getting so inexpensive it is hard to justify not getting one. Several years ago when I bought my first one I believe it was just under $100 and I was always impressed with it for that price. When I started shopping for one recently for the 4Runner I was impressed to see that prices have came down even more and features have gone up.
This is the unit I picked up for the 4Runner for less than $50: https://amzn.to/2nuEaXu
It is nearly identical in form factor to the last one I had and I believe most likely made by the same company. The last one worked so well it was an obvious choice again. Install can be as simple as plugging it into the cigarette lighter of your vehicle with the included cord or hard wiring. I chose to hard wire for a cleaner install. Fortunately wires are simple to run in the 4Runner and tapping into the fuse box is straight forward. This dash cam now turns on and starts recording with the vehicle and shuts down a few seconds after you turn off the ignition. It is basically all automatic with no need to do anything.