There is incredible variety available in gold bars ranging from 1 gram up to 400 oz. (and beyond, I'm sure). I don't own a single one.
If I did, I can't imagine having one over 1 kilo. That's over 32 oz., so you can ballpark how much it sells for. I just don't see me with that tied up in one bar.
The single gram also is not for me. It is selling tonight for almost $49. For that price I can buy a roll of 40% silver Kennedy half dollars for less than spot price, and the Kennedy half dollars are easily divisible and widely recognizable.
Probably the only size bar I'd ever want is a 10 oz. Johnson Matthey has one that is .9999 fine, and is currently selling for about $20 per oz. over spot price.
If I ever buy a gold bar, this will likely be the one I choose. It’s sort of a goldilocks size. Small enough that I don’t have to sell the house to buy it, but large enough that the premium over spot price seems reasonable.