After a few short years coming to grips with the sharing economy—not exactly "embracing" it as Airbnb press releases may suggest, but not exactly coming down on it with a hammer—the city government of Berlin imposed an official ban on subletting unregistered vacation apartments to tourists in May 2014. Airbnb hosts were given until that August to register existing listings. An estimated two-thirds of them did not.

Last October, the New York State Attorney General launched his own broadside against the San Francisco-based startup, in the form of a statistical study intending to demonstrate how the business was driving up rents and putting hotel owners out of business (adding insult to injury by weakly parodying Airbnb's graphic design in the report). According to the evidence amassed, he pronounced the majority of listings illegal.

Yet as in Berlin, enforcement is where anti-"sharing" legislation hiccups. City bureaucracies are hardly as agile as tech companies, and the dance between the two is painfully awkward. Municipal governments and startups around the world are frantically conducting surveys like New York's in the hopes of legislatively anticipating the effects of Airbnbs and Ubers: the former are hustling to update existing legal systems in accordance with new technologies and the economic arteries they provide; the latter are hustling to get ahead of those laws before they are put into action.

With or without legislative effect, the surveys are there, and they are full of disturbing information. From reading the most recent detailed report on Airbnb in Berlin, where I live, I learned, among other close-to-home tidbits, that the number of probably-now-illegal Airbnb sublets in my neighborhood, Reuterkiez, tops any other neighborhood per capita in Berlin, and therefore in Germany. Never mind what this says about my cultural capital (probably negative; you never want to be at the center of the swarm), but the effects on the amount of actual capital circulating on my block are enough to to give one pause.

The report where I found this info is by a group of students in the design department at Fachhochschule Potsdam, titled "Airbnb vs. Berlin—Was sagen die Daten?" ("What does the data say?"). For practice in making infographics, they took a small data sample (January 11—February 2, 2015) from Airbnb's front end and splayed it out in charts and maps across an interactive website, with accent colors only a shade away from Airbnb's trademark salmon pink (Airbnb: #FF5A5F; Berlin: #FF656A). 

Yes, this is a student project, and no, it is not comprehensive. But for those with a vested interest (me), the basic pink data points are useful for tentatively trying to grasp the general situation, and perhaps more useful in demonstrating how hard it is to pinpoint any actual causality between Airbnb itself—whose influence until now I have mostly felt rather than sought to quantify—and any particular façet of the (worsening) urban situation.

Map from www.airbnbvsberlin.de showing streets with high density of Airbnb rentals.

Statistics are already in place to demonstrate that rents are sliding uphill, hotel profits are (likely) going down, longtime residents are being edged out of the city center, and the sorry state government is missing out on a potential bounty of property taxes. Here are three bullets on Airbnb, sourced and translated from airbnbvsberlin.de, to correlate with the above facts as you see fit:

• Any way you slice the data, Berlin is the "undisputed Airbnb stronghold" of Germany. 11,701 Berlin listings were active during the span of the study, compared with runner-up Munich at 4233. The available Berlin apartments amounted to approximately .4% of available domiciles in the city. These included a total of 34,418 sublettable beds.

• "Legitimate" rents are rising rather in Berlin quickly in comparison with other cities in Germany, and the supply of long-term rental housing is going down for those who want live in the city longer than the "Wochenend-Easy-Jet-Partyvolk" (after whom one Airbnb listing is titled). The average Airbnb listing costs 55 Euros a night; renting a one-bedroom place for a month costs on average 650 Euros a month. Why rent monthly if you could net the same in 11 nights? (See these maps comparing the availability of vacation to long-term rentals for further adorable visualization.)

• At the crux of the New York study and others has been the issue of whether DIY hoteliers are really amassing real estate across cities and running fully fledged businesses serviced by Airbnb, rather than operating as "hosts" out of their private homes. Thus a particularly contentious statistic is the number of hosts with multiple listings to their names. The numbers in Berlin, according to this source, are comparable to those according to the NY attorney general: 1.3 listings per host compared to 1.2. This is a small percentage of hosts overall, but that small sector is nonetheless netting a large profit.

If you are contemplating these facts and feeling neither perplexed nor enlightened, you are not alone. As Mark Gimeon wrote in Bloomberg of the NY Airbnb study, "If you are looking—as New York State regulators seem to be—for evidence that Airbnb involves much bigger operations than a few students renting out their couches, it's in the[ir] report. On the other hand, if you prefer to see evidence that the hosts on Airbnb are still largely mom-and-pop, or mom-and-mom, or starving twentysomething, operators …you'll find that, too." It's both and neither economics and sharing.

What I can share is this. I'm writing from a room in Lisbon that I'm subletting from friends of friends. While I'm here, a friend is subletting my room in Berlin for almost exactly the same amount of money I'm paying for this one. Though we have each used Airbnb in the past, this time all plans were made via friend networks. Thus we charged each other less than market value and avoided sending a percentage cut to San Francisco. The liability insurance and the secure monetary transaction Airbnb provides were skippable, because some semblance of accountability is supported by the unstructured social web via which we know each other.

And so, if the key role of Airbnb and all such intermediaries is to stand in for and effectively expand that web of accountability, and if it is in your interest to earn the same amount for a room as you pay for another, and if, as Michel Doermer, a Frankfurt spokesman for Uber, says, "you can't put the brakes on progress," and if progress equals increasing income stratification, then your best hope for the future is simply to not break your friends' shit while you sublet their rooms without a formal agreement. (That's not aimed at you, Jonas).