Another thing to think about might be your liability if one of your helpers get hurt. Its easy to say a friend wouldn't do that, but a friend that can't work or worse may have too.
I'll be hiring someone insured when I get one.
Remember to let physics work to your advantage. The only time's I've had problem lifting something heavy is when my help wanted to dead lift it into the truck after we used other means to get it out of the house. Use a ramp, a hand winch, whatever you need to, but don't try to pick it up.
Also, 4 guys on a thousand pound safe is NOT equal to 250 lbs each. There is always at least one guy who will have more of the load because of the way everyone moves together. It can be done safely but use a strong dolly with solid tires and ramps to get it into the truck.
If you absolutely have to lift the safe up off the ground get a lifting strap (or two) so that the weight is carried by your legs. Most folks can squat a lot more weight than they can reach over and pick up. This is how refrigerator delivery guys do it.
Lastly, the issue of floor support. Consider the weight and the bottom surface area of your safe, and divide to get pounds per square inch. Next, consider the area of your feet and your weight. You will find that most safes have less pressure than you expected. Simulate this by having a bunch of, er, rotund, people stand in one small area. The house doesn't cave in, does it?
Apples and oranges as people are not a dead load they are a live load with the ability to move and never "sit" in one place for years. Also most rotund people can move out of a house on fire and are not likely to stay long enough for the floor joists to burn out from under them (if they do, they are dead) thus causing the floor (which is now the only thing supporting them) to collapse thus sending them on to my head.
You have friends that actually work Mine just drink my beer and shoot my ammo
Two of my friends hired a professional safe mover, said he wasn't too expensive. Depends on how many stairs, distance, etc.
For what it's worth, Call SAFE-JIM 260-417-1345
Shouldn't cost to ask for a quote, then decide.
The said he picked up their new safwe at the store, delivered to their house and put it in place for something like $135. Sounds safer than hospital bills or a damaged safe.