First, if you're going to concentrate on silver, you don't need to worry too much about fakes. Gold and - surprisingly - large copper from the early Empire are more liable; copper is very hard to find in good condition and the pieces are quite large. Compare that with small bronze from the later Empire such as Constantine, which survive in enormous quantities.
Roman is not hard to find especially silver (denarii and antoniniani) and small bronze, and you can pick up examples in quite high grade for what seems to be modest outlay. For example, imperial denarii of non-rare emperors can be found in EF for often less than £100. Huge numbers were minted and many are found and put up for sale. Hence the lower chances of being faked.
These coins are "ancients" rather than "hammered" as such, even though the minting methods were similar. They tend to be quite a lot thicker. Silver quality varies a great deal, and the antoninianus (similar to the denarius but lower denomination) ended up being merely a silver wash over bronze. That does not of course make them less collectable.
Then you have the Republic (BC; pre-Augustus) where coins were struck in lower quantities and are consequently pricier. It's almost a separate area of collecting