Actually I read the whole thing - it was written really well. But it's far from extremely clever what he did. Anyone who's studied tenancy law for more than a few days could do the same. The only difference he had was being sociopathic enough to do so - a point which the article makes in the end when he turns out to be a murderer. Furthermore, none of the above are in any way related to engineering or hackernews, and it's completely off topic for this site.