Revelation 13
16 And he causeth all, both small and great, rich and poor, free and bond, to recieve a mark IN their right hand, or IN their foreheads: 17 And no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name.
At what other time in history have we had the capability or technology to use a 'mark' to monitor financial transactions?
To start with the majority of Bible translations do not use "in" - they use "on" or an equivalent wording (I checked 16 on biblegateway.com - excluding the NIV-UK as being redundant and getting no result for NLV - only 3 used "in")
As for the technology required we need:
1) The ability to make a permanent mark on human skin. Tatooing and brands have been around for a long time. Since the mark is described as being a representation of the "Beast"'s name or number this is clearly adequate.
2) Money. That was also well-established even by the time of writing.
3) The ability to make and enforce laws.
All of thse are well within Roman capabilities.