Having started a chain of hostels in India, I think the hardest part is starting the first hostel. Once you've got the first hostel operational, you've been through the grind and know what to expect from the second and third.
The advice I would give you is to give yourself the best possible odds of success with the first hostel. Pick a place with the least amount of competition, build a business plan that would succeed in the worse case scenario and start off in a market (location) that you understand the best. Having lived in Singapore, Indonesia and India, I am familiar with the ground reality of businesses in these countries and would be happy to help. Drop me a note if you have any questions.