Subletting one’s home or renting out space on your own property has long been a way for some Los Angeles residents to earn some extra income without telling the taxman. And the rise of home-sharing services like Airbnb and VRBO has only encouraged more people to make money off their unused rooms. But the city of Los Angeles is now sending stern reminders to people who list properties on these sites that they have to pay taxes similar to those paid by hotel operators.

The L.A. Times reports that the city has begun sending warnings to residents advertising rentals on Airbnb and other sites that they are to collect taxes from guests on behalf of the city.

Additionally, city regulations [PDF] on these taxes state that, “The amount of tax shall be separately stated from the amount of the rent charged and each transient shall receive a receipt for payment from the operator,” and that hotel operators are not allowed to state in any manner “that the tax or any part thereof will be assumed or absorbed by the operator, or that it will not be added to the rent, or that, if added, any part will be refunded except in the manner herein provided.”

So someone advertising a room in L.A. for $100/night can’t tell the tenant, “don’t worry about the taxes; I’ll just take it out of my cut.”

The big problem for the city has been that it’s become very difficult for officials to track down contact info for the landlords who list properties on Airbnb. It’s “like looking for a needle in a haystack,” explains the assistant director of the city’s office of finance to the Times.

And so the city has decided to send these warnings online directly through the websites.

“It might very well be that a lot of these folks are just not aware that they even have the obligation to pay,” said Councilman Paul Krekorian. Now these hosts can’t plead ignorance.

But a rep for Airbnb tells the Times that it already informs hosts to their tax responsibilities and that the site has an L.A.-specific section on its Responsible Hosting information page.

Looking at this section, it only states that both L.A. County and the City of Los Angeles impose transient occupancy taxes and directs hosts to the appropriate regulations for each. One could argue that Airbnb could provide more helpful information to its hosts in L.A.

These types of services have come under fire in various markets around the country. In addition to issues of unpaid tax obligations, some residents have complained about Airbnb landlords using the site to turn vacant homes into de facto hotels, with new tenants constantly moving in and out.

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