Some people prefer home-sharing services like Airbnb over hotels because they would rather stay in a cozy apartment than in a sealed-up room with of a chain hotel. Others choose these services because they feel they are saving money over the cost of a traditional hotel, but how much you save — or if you’re saving at all — depends on where you stay and how you book your hotels.

The folks at Priceonomics.com have posted a pretty nifty, if flawed, comparison of median hotel rates vs. Airbnb averages in a number of U.S. markets.

As expected, the most expensive cities for hotels — New York, San Francisco, Boston — are also the three priciest places to rent an apartment from Airbnb. Of this trio, the biggest savings are to be had in San Francisco, where a rented Airbnb apartment will run you $165 for the night, which is around 72% of the median hotel room rate in the city of $229.

The one huge hitch in this study is that this comparison uses rack rates for hotel rooms, and not the prices that are readily available to consumers through booking services like Hotels.com, Travelocity, Priceline and others. For example, a quick search on Hotels.com of San Francisco turned up more than 100 hotels in the city with published nightly rates of at most $200. Even when restricted to 3- and 4-star hotels, there were at least two dozen places with rooms at or below the $165/night rate.

Meanwhile our Airbnb search for full apartments in San Francisco resulted in more than 140 places renting for at least $170/night, with some going for several times that amount.

For a more middle-of-the list city like Philadelphia — 17th most-expensive for hotels ($149) and 13th most-expensive for Airbnb ($125) — the price difference is slightly more distinct, though not as huge, between the two. Even when comparing Hotels.com rates for places to stay in Philadelphia, there were only a handful of 3-or-more star hotels available for under $150, and only a few dozen Airbnb apartments going for a nightly rate of more than $150. Thus, the difference seen in the chart at the top of this page reflects reality more accurately than it would for a city like San Francisco.

So while the Priceonomics comparison is a helpful starting point, remember that these numbers are averages, and that prices will vary wildly within each market. This is especially true for Airbnb, as some spaces offer multiple rooms and/or desirable amenities that can drive the price up, while some people keep their prices low to ensure that the rooms are occupied as often as possible.

Additionally, it’s a bit of comparing apples and oranges, or maybe comparing Granny Smiths and Red Delicious apples, as a hotel room rarely offers more than the bed, a couple of seats and a bathroom, while an Airbnb apartment usually includes a sitting room and a kitchen area. You could compare room-only Airbnb rentals with hotel rooms, but those offerings often include a shared bathroom and other communal spaces, so again it’s not a true one-to-one comparison.

In the end, it all comes down to what you want to pay and what you want to experience. Almost all cities have hotels running the gamut from fleabag to four-star, and you’re likely to find the same range of size, quality and comfort among Airbnb offerings. You should do as much research as possible about either option before plunking down your money, because nothing ruins a vacation faster than having a crappy place to come back to at the end of each evening.

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