starting a transport business, Siena vs bus, budget 1million, which is better for a starter , and one can I get neat used buy and drive with this amount. and which year

A bus is obviously going to take more passengers than a Sienna. You might consider using it as an Airport shuttle.

The Road is decent (at least in Lagos) and fewer agbero wahala.

This advice might also help;

Transportation

People must move from their homes to places of work within and outside cities. There so many ways to enter this business from Uber to commercial buses to tricycles. The most important factor for success is either you drive your vehicle yourself if it is only one you have or find trustworthy people to drive your vehicles if you have more than one. Hire purchase agreement with your drivers is an option you might want to consider as it gives them an incentive to reach the agreed sales price in record time. This is good for you as you can use the profit to expand your business.

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