On a side note, something I've been looking for for many years is a simple, no frills, cheap room rental service across the world's largest cities. Of course, now there's Airbnb, but I'd prefer one company that administers the living locations + design/look of the rooms, if that makes sense, rather than a network of regular people using a site to rent out their places. Basically, I want to know exactly what I'm getting (ie, same price, size, amenities, ease) no matter which city I go to. Like a hotel chain but for short, middle, and/or long term rentals.
Caravanserai looks like a promising start, though I'm also aware of the effort + price points from living abroad (I'm currently in Lisbon), and it's about 50-60% less than the lofty $1,600 mentioned (however, a co-working space here is around $220/mo, and I didn't include this factor in my estimate).
All that said, I am quite the stickler but surely most people won't mind paying the currently-set price.