Here's how you do it: disallow custom ISOs, and only provide ISOs with a modified version of the stated OS. What modification? The command "free" always returns 8GB total even if it's running 256MB. Serious users who actually bother picking one up won't trust it enough to use it, non-serious users who get it just for the "elbow room" won't need/use anywhere near the 8GB, and legit uses that would use all the 8GB are disallowed, VPS immediately shut down if such usage is detected. Actual node has maybe 64GB of RAM, located in, say... Buffalo!
Seriously, though, since this is AnthonySmith, I imagine that either he's not actually planning to go through with this or he'll pull it off, possibly at a loss until hardware gets cheap enough to pull a meager profit. Maybe cut corners by only providing one IP free until you give a really good justification for the second. Either way, I'm just gonna wait and see.