Hehe, it’s usually the first question people ask. The answer is: it varies incredibly from one coin to the next, depending on rarity and quality. Most people assume that since these coins are between 2000-1500 years old, it means they must be priceless. But the reality is that the Roman empire was around for a VERY long time and had a vast economy. They minted millions upon millions of coins, probably more than any civilization until our modern days.

You can have silver denarii or antoniniani (“double” denarius) for as little as 15-20 bucks. The really rare ones go up to the high hundreds and even the low thousands for silver and bronze. Golden coins (aureii) are more rare but usually in great condition, but will set you back several thousands in even the low spectrum.

If you really just want “a roman coin” and the only requisite is that it’s genuine, you can get late Roman bronze coins for like a buck a piece, or a couple dozen at most for very nice specimens. Just be careful with Ebay and the like, lots of counterfeit going on there. If you go for the cheaper coins though, there’s little chance of fakes since they’re simply not worth faking.