Well... you cannot divide gold, unless you are using it specifically for barter. In today's market, if you split the gold bar, people will buy it from you at a lesser value than if the bar was whole.
If you sell the gold whole, I don't know of anyone that will buy it for it's true value in weight.
The best strategy for gold is buy and hold until the buyers will offer more than what someone bought it for.
It's based on the current spot price. Depending on the form of the gold, you can sell very quickly to a trader at a little higher or lower than spot, I'd say 1-2%?. You'd get more if you sell directly to someone, but that's risky of course. Retailers sell at a premium above spot, around 3-4% for regular bullion and more for coins like American Eagles or Maple Leafs.
