I must say that idea is quite interesting but it won`t be easy to to create. In generously speaking car rent is required in my country - Latvia, but in small cities we don`t have it or cars are in bad status. I read in roadman that you are planing to introduce your project in Latvia, Estonia and Poland. I don`t know about other countries but in Latvia this idea could live. But it will be very heavy job. For people in Latvia it will be very non-standart method, they like old methods ) I only can wish good luck to team!