Character holding and releasing an object

I’d like to animate a character grabbing a stationary object, holding it while moving for some time, and then releasing the object. I’ve considered using the “Child of” or “Copy Location” constraints on the object, and setting the influence to 0 when the object is not being held, and 1 when it is being held. This works before it is grabbed, and then while it is being held, but then once the object is released (influence set from 1 to 0) the object returns back to its original location instead of staying at the last point it was at before it was released. How can I get the object to be held by a character during part of an animation but then have it be released later in the animation, and have it stay at the location that it was at right before it was released?

Have tried inserting a key frame for it’s final resting location?

It would work if I inserted a location keyframe right when the object gets grabbed, and then moved the object to the location at which it would be at the frame at which it was about to be released, and then inserted another keyframe at that frame. However, in this case I would have to guess the location it was at right before being released. If I get the location slightly wrong, the object would noticibly jump a little bit from one point to another as it is being released.

I made a scene of the like (but can’t grab it for the moment).
I used an Empty parented permanently to the character’s palm and rendered the sequence when the object was grabbed and carried with the object temporarily also parented to the Empty (you’ll probably have to play around with the offsets settings to get the object placed as wished).

Hope it helps