My safe is in a restricted area (an alcove). I pulled it out once to paint the floor, so I've had the pleasure of installing it twice!
In both cases I removed the door. On my safe it's just a matter of opening the door and lifting it off the hinge pins. No big deal.
To move it I tilted it over at 45° and "walked" it right into the alcove. It was surprisingly easy SO LONG as I kept it on its balance point! The safe didn't get away from me, but if it did, my contingency plan was to GET THE HELL OUT OF THE WAY!
The second time I installed it, I slid it in on "Moving Men" furniture slider pads. The pads only lasted through the one job as I had them way overloaded. But they did the job. And I was actually able to remove them using a Porta-Power and toe jack. I rented the Porta Power for another job, and had it for the day, so it was handy.
When bolting the safe to a concrete floor, my recommendation is using Hilti anchors instead of Red Heads. Red Heads leave the stud protruding above the floor -- so good luck ever getting that safe back out. The Hiltis are sub-grade, so when you remove the bolts/studs it's like they were never there!