The most sensible thing to do is to buy precious metals at a price that is as close to the spot price as possible. If you buy gold, bars are the most attractively priced. Gold Coins are a bit more expensive to buy, but also yield a bit more when sold than Gold bars. Bee silver the choice is mainly determined by VAT. As a private individual, you pay the high VAT rate of 21% on silver bars. These bars are only interesting if you can buy them for business purposes. Cheaper are the pure Silver Investment Coins which are legal tender in the country of origin. These coins can be traded under the margin scheme, which means that tax is only charged on the profit margin. This makes the coins, despite the higher production costs, a cheaper alternative. You can also Buy Dutch silver coins, because it can be traded free of VAT. This is the cheapest way to sell physical silver.
Keep in mind that some coins may become collector's after a number of years due to their limited mintage. Consider, for example, the golden Chinese panda and the Silver Kilo Coins of the Australian Perth Mint.