Where is there source code available for a ride sharing app? How much is it going to cost?
How many developers will you hire? How many customer service representatives will you hire?
How much is insurance to cover the drivers going to cost (standard auto insurance usually doesn't cover them when they act as a Taxi).
When Uber/Lyft start in new cities, they tend to give out 10+ free rides to early customers in order to get new people to use it and spread the word. How much will this cost?
When Uber/Lyft start in new cities, they need to incentives drivers to drive for their platform even though there aren't many customers yet. They will often pay them an guaranteed hourly rate at the beginning. How much will this cost?
As a customer, why would I take your service instead of Uber/Lyft? With Uber usually I can find a car within a few blocks of me. It won't be the case with your service. Even if you aren't taking a cut of the profit I don't see your service being at a competitive price.