How to do a real time changeable offset?

How can I add an offset to an object so that it can be adjusted while the game is running by changing the offset values in the inspector?

I tried this:
object.transform.position = object.transform.position + offsetVector3;

but its causing the object to animate and fly off the screen presumably because its being called every frame in Update, so how can I have it update in real time but also stay put?

So the issue is that your adding the offset to the position every frame like you said. Picture this in 1 dimension.

frame 1. position = 0, offset = 1 so new position = 1
frame 2. position = 1, offset = 1 so new position = 2
frame 3. position = 2, offset = 1 so new position = 3

It will keep adding the offset every frame.

I would fix it be storing the original position at the start and adding the offset to that.
frame 1. original position = position
position = original position + offset
frame 2. position = original position + offset
frame 2. position = original position + offset

that way it’s stable.