From my first encounter with Airbnb I have been a fan. I've used the service and then extolled its virtues. I've been a kind of evangelist, convinced that my most hotel-obsessed friends would catch Airbnb fever if they just gave it a chance.

I've used Airbnb close to a dozen times in total. Until recently, it was difficult for me to perceive any potential weaknesses for guests within the service. (Hosts are a bit more vulnerable than guests, as highlighted by that particularly well-covered and quite terrible incident last year. To its credit, Airbnb introduced a $50,000 vandalism and theft guarantee in response to that event.)

I recently discovered a weakness of Airbnb for guests, which I'll try to summarize as the uneasy pairing of a host's limitations and a guest's expectations.

Here's my example. A few weeks ago I rented an Airbnb apartment in an exciting corner of a big city. There were two issues with the rental: a miscommunication around the key, which led me to the conclusion that the host only possessed a single set of keys to the flat, and a strong hint that the rental was not approved. My evidence for this latter assumption was that the house rules instructed guests not to answer the front door and to tell neighbors, if asked, that they were friends of the owner.

Here's the thing, the key misunderstanding and its terrible inconvenience for my host aside. Given the choice I would never have opted to stay in a clandestine rental, and nor would I have wanted to be the sole key holder of an apartment owned by somebody I had never met. Unwanted complications almost seem to be guaranteed in such situations.

For me, the beauty of Airbnb has been the friendly, effortless simplicity of the experience, with the happy bonuses of local knowledge and invitations to coffee. But with the stress of feeling that the single set of keys in your possession is your host's lifeline to his living space, or the worry that your very presence in your host's building is clandestine, the experience begins to feel neither effortless nor simple.

And this is the crux of the issue. With Airbnb it's hard to know in advance whether your needs as a guest will match up with the particularities of a host's situation.

[Image: Alex Robertson Textor]

Silba is a tiny northern Dalmatian island close to the port city of Zadar, Croatia. The island sees its population boom in the summer, from a few hundred year-rounders to a few thousand seasonal sunshine seekers. Closed to passenger cars, Silba is one of many Croatian islands that could have been created to perfectly showcase summer in all of its glory.

This image, captured by Flickr user mmusnjak, is drenched in happy summer emotions. It is a particularly bittersweet image today, the last day of summer in the Northern Hemisphere.

Upload your best images to the Gadling Group Pool on Flickr. We select our favorites from the bunch to be future Photos of the Day.

Baffin Bay, located between Greenland and Baffin Island in the Canadian territory of Nunavut, is a desolate and beautiful place.

It is also very far north. Though the above image looks like it might have been taken in the dead of winter, it was actually snapped in late August of this year. Check out photographer island602's big set of images of the Arctic for more near-frozen delights.

And upload your photos of icebergs and other frozen things to the Flickr Gadling Group Pool. We choose our favorites from the pool at Photos of the Day.

The Golden Gate Bridge, which links San Francisco and Marin County, is one of the most iconic man-made sights in the United States. It's bold and dramatic, the source of rich symbolism and the background to countless tourist snaps. In this image, taken by Flickr user jrodmanjr, the bridge is dwarfed by a cliff and the humans atop it.

Do you have an image of a major tourist site? Upload it to the Gadling Group Pool on Flickr. We choose our favorites from the pool as Photos of the Day.

Souvenirs are tricky for business travelers. It's all too easy to be overwhelmed by work or a busy itinerary only to find yourself grabbing something in duty free in the airport – or stopping by a gift shop to purchase an anonymous object created 12 time zones away from your destination. A T-shirt of thin cotton made in Bangladesh that says, "I Heart Vienna" may be fun in a kitsch sort of way, but it's not really a good souvenir.

To find a good souvenir, be guided by this question: What is produced locally? Think about "production" broadly – in addition to crafts and art objects, think of clothes, food, accessories, and housewares. If you're in a destination where very little is made, move on to this follow up question: What is collected locally?

By frequenting flea markets and local arts and crafts stalls, you can find locale-appropriate souvenirs of great and enduring value. Guidebooks and hotel concierges can direct you to local markets, flea markets, galleries and other shops where items of local value can be found.

Lastly, by paying attention to the beauty of the incidentals of your surroundings, you might very well chance upon the most sentimentally valuable souvenirs of all – commonplace objects designed markedly differently than comparable objects at home.

1. Local products. Pricing, materials and goods vary radically from place to place. An item created by artisan producers local to your destination – assuming high quality, of course – expresses the culture of a place powerfully.

2. Flea markets. The strangest cast-offs can be found in flea markets. Sometimes these objects are prized antiques, and other times they have virtually no value, having just been dragged from a heap at the bottom of a closet. But there's no better way to get a sense of a location than at a flea market or its local equivalent.

3. The incidentals of your surroundings. What actually triggers memories and nostalgia? The ticket stubs, paper menus and products that you come across on your travels. That glass yogurt container. That tram ticket. That theater program. These objects can be framed, used as scrapbook materials, or simply displayed at home. These objects permit a thoughtful, if passing, consideration of the fact that travel creates opportunities to reconsider the incidental trappings, the very packaging, of our lives.

[Flickr image via laszlo-photo]

Tel Aviv's street art – in addition to sabich of course – was a highlight of my visit to Israel and the West Bank last spring. I snapped graffiti, spray-painted eggplants, political stencils and stickers.

Clearly I wasn't the only one to find this element of Tel Aviv's public culture interesting. Flickr user AlexSven photographed this complicated image in July of this year.

Upload your favorite images to the Gadling Group Pool on Flickr. We choose our favorites from the pool to be Photos of the Day.

Mongolia looks like the perfect place for a road trip. This image, according to its photographer Mark Fischer, was snapped between the Mongolian capital of Ulaanbaatar and Mandalgovi, a small town perched on the edge of the Gobi Desert. The bright yellow of the broken-down car, the blue sky, the ramshackle buildings, the green earth, the machinery dumped here and there – little of it suggests tourist board boilerplate, granted, but every last detail speaks to Mongolia's compelling geographies and vast distances.

Upload your best images to the Gadling Group Pool on Flickr. We choose our favorites from the pool to be Photos of the Day.

Skradinski Buk is a natural pool with waterfalls located in Krka National Park in Croatia's Dalmatia. The area of natural beauty is visually arresting enough to wrest seaside-focused tourists inland for a few hours. This fact by itself is really saying something, as the Dalmatian coast is exquisitely lovely in the summer.

This image was snapped by Flickr user mmusnjak, who has lots of other great photos of Croatia and Bosnia-Herzegovina in his Flickr photostream.

Upload your best images to the Gadling Group Pool on Flickr. We chose our favorites from the pool to be Photos of the Day.

Over the last decade, Greenland has opened up to increasing numbers of tourists. The Danish territory, with new powers of political autonomy as of 2009, inspires adventurous travelers with its extreme weather and dramatic geographies. Greenland is also incredibly expensive to visit, as there are no roads connecting towns and settlements along the coast. To get from town to town, one must either fly very pricey Air Greenland or travel by boat.

The easiest and least expensive way to visit Greenland is to book a day tour from Iceland to the Eastern Greenlandic island of Kulusuk, which is a 110-minute flight from Reykjavík's domestic airport. The day trip is not cheap. It runs €533 ($654) though August 20, and from August 21 through September 8 it is priced at €477 ($585). The day trip gives participants a guide-accompanied walking tour from the airport to the village, about an hour of free time wandering around the village, a tour of the village church, a brief discussion of Greenland and a viewing of a folk dance performed by a Greenlandic man, translated by the guide. The tour itself lasts around five hours.

The tour finishes up with a boat ride through an iceberg-laden bay back to a bit of shoreline adjacent to the airport. This boat ride, an inarguable highlight, costs an extra 150 DKK ($25).

Dunedin, with a population of over 115,000, is New Zealand's southernmost big city. (No disrespect to smaller Invercargill and other southerly towns.) For visitors to New Zealand, Dunedin feels like the real south of the country.

Flickr user carlcroom's photo of Dunedin's train station offers a little bit of a sense of that South Island end-of-the-road magic. Mostly, though, he simply captures the grandeur of an impressive train station. Dunedin's, finished in 1906, was built in a Renaissance Revival style.

Upload your favorite images to the Gadling Group Pool on Flickr. Our favorites from the pool are chosen as Photos of the Day.