Why did you decide to choose carsharing, house sharing and freelance? Why these spheres, not selling personal stuff?
The things is that sell you stuff or buy somebodys one you can with the help of Craiglist absolutely for free, without any commissions and risks, even for fiat money. Blockchain will be in this sphere soon, but we think that it is more required in freelance and sharing because of the potential utilization of smart contracts with well defined conditions, availability of guarantee and insurance deposits, dispute solving tools and low commissions. All bullets mentioned above will affect on freelance and sharing markets - they will become more accessible and simple. And, of course, it will increase the level of trust between vendors and customers.
Sounds reasonable. But, for example, on Craiglist I can buy whatever without commision. Ebay has commissions. Maybe it would be better to creare Ebay on blockchain?