I have one of these bolted low on the side of my 300+ pound "night stand" located next to my bed for my EDC/night unit:
For the vehicle, my daily driver for 10+ years was a pickup truck, with several convenient aftermarket gun safes available that mounted under the center jump seat:
There are shallow aftermarket safes available for other vehicles, if you want to cut a hole through the floor and throw a floor mat over it. I never looked at BMW options, because I only drive it to work and entering the grounds with a weapon (even in a locked safe) is a felony. Plus, my BMW is a rolling battery pack with a carbon fiber chassis, so cutting through the floor isn't an option. I always take the pickup when going to the range, since it blends in better in the parking lot.....