I interviewed with them a few months ago. The guy who interviewed me was super nice and really smart, but the company's business model seemed really odd. It was some sort of arbitrage on cars with dealerships owning most of the stock and trying to guess when the best time to sell the car as used was. Plus they had this belief there was some customers who wanted something between ZipCar/rental cars and a traditional lease, which I found dubious. I can see wanting one year leases, but below that seems like a pretty tiny market. I'm not surprised they've mostly switched to focusing on Uber.
There's a market for people who need a car to match their short term housing. (<1yr, or even a 3-yr lease on a used car). This is Rent-a-Wreck's market. Not a huge market, though.
This doesn't make a lot of sense to me, don't competitive pressures mean you implicitly pay for the sales tax you're not explicitly paying when you lease?
In my state (although not all) you get credit against sales tax for a trade-in. But it seems to me that's a primary reason why a dealer offers less on a trade-in than a private party would. Just because you're not paying sales tax doesn't mean you get the whole benefit.
These businesses seem highly appealing to financiers, as this is largely what financiers do in their day to day - and it seems to work out well for them.