Have there been any buyer-centric, bounty-based services that worked?

You usually only recognize the commissions as revenues and use the term "Gross Merchandise Value" (GMV) to describe the size of the marketplace (value of all transactions going through the site)

I like to separate your question into 2 sub-questions: #1 How do we determine which side to charge? #2 How much is the right amount to charge? On #1, my answer is that you can charge the side(s) for whom you add the most value. In your examples, Uber really solves a big problem for drivers, it's that they sit idle for a good part of the day, so are willing to pay a lot for new leads. (their alternative is no work) Consumers are charged more for the convenience of a private car but they are probably not so much willing to pay more for a taxi, even if they can hail one from their phones. For AirBnB, it's a mix, it's a way for landlords to monetize idle capacity which they are willing to pay for, but it's also a way for a renter to pay less than they would normally pay for a hotel. On #2 (how much), I like to triangulate a number of factors: - What's the maximum amount I can charge one side, while still being a good deal for them. - How much do I need to charge so that I can become profitable? (the economics are quite different if you charge 3% vs. 12%) - What are comparable services charging for substitutes/competitive offerings? I will just add that there is no formulaic way to determine pricing strategies (curated vs. open), and it's a lot more about what's the comparable and what the value delivered is. That's how I approached the question while deciding the business model at ProBueno.com (my startup)

Your pricing model should hinge on the fact that the perceived value of services should outweigh the cost associated with it. You can consider looking at online marketplaces like Craiglist, Kijiji, Airbnb, etc to understand various types of business models. However, the approach shouldn't be based on what others are doing. Rather, you should understand your niche, values associated with the niche, and adopt appropriate pricing model. Invest your time in designing the business model for your startup, followed with reviewing it vis-a-vis other models. Need help with business model? Feel free to reach out.

It's very important. (first, read this article by Josh Breinlinger - http://acrowdedspace.com/post/47647912203/a-critical-but-ignored-metric-for-marketplaces) The way you achieve success in a marketplace is by driving liquidity for both your supply & demand. Demand-side Liquidity = When users come to your marketplace, they can achieve their goals. Supply-side Liquidity = When supply comes to your marketplace they can achieve their goals... which are almost always to make money. If you're making a large amount of your supply-side users a full-time income, then you're helping them achieve liquidity. Now it's not so black and white and it doesn't always have to be a "full-time income." It depends what their goals are. E.g., 1) At Airbnb, renters aren't looking to quit their day jobs and become landlords full-time... they're just look to earn a substantial amount of income to offset their rent, mortgage, etc. So in this case, I would probably goal on # of renters that earn >$500 / month... and (in the first 1-5 years) try to grow this number by 10-20% MoM... and maybe by just 5% once you're in the mid-high tens of millions in yearly revenue. 2) At Kickstarter, the goal of the supply-side is to get their project successfully funded. They don't care if the project creator is "full-time"... they just want to make sure they meet their funding goal. This is why they talk about their 44% project success rate all the time - http://www.kickstarter.com/help/stats 3) At Udemy, our instructors want a substantial amount of their income to be driven from their Udemy course earnings... so we look at how many instructors are earning >$2k / month.

For me personally, no. However, what you really need is a larger data set. Gumroad just did a post on prices ending in "9": http://blog.gumroad.com/post/64417917582/a-penny-saved-psychological-pricing 37signals started with prices that ended in 9: http://37signals.com/svn/posts/1287-ask-37signals-how-did-you-come-up-with-pricing-for-your-products ... but they later did research and found it didn't matter (for them). The answer for YOU will likely be to test these things for yourself on your SaaS app.