You decide how much is needed to sleep safe.
My garage has:
Camera inside routed to a web address with password entry. Automatically sends 30 seconds of images from before and after a motion detection to my email; which pushes to my phone.
Additional locks on both garage door rails. Asec Garage Door Bolts
Power switch in residence for all power in garage (garage door opener and power cutting tools wont work without access to residence).
Emergency release on garage door, tack welded.
Deadbolts on door to residence(Key on both side).
Alarm on both garage door and main door.
Ground Anchors. Bikes are always locked down. I have this for my bike
Y anchor - the Ultimate Motorcycle Security Ground Anchor
I have a couple surface mount anchors for visitors.
Sign inside stating. Smile you're on camera with arrow pointing to camera one of the cams. Interesting how when someone walks in garage they always look right at camera that way.
My favorite are my torso/head silhouette rifle targets from the range on my wall. Labelled from 100yds, 300yds, 700yds, 1000yds. Along with a few various rounds on the gunsmith bench with a couple Barret 50 cals sitting on end.
There's a few other tricks, but I'm not giving away all my secrets.
Could my baby still vanish? Yes
But, I sleep well at night now.