Get real online paid registrations for a seminar

We are planning for paid seminar with a ticket worth of Rs. 200 each and we want to make sure that around 50 registrations are done online. And the registrations are required only from a single city in India. This seminar is purely a management seminar which will be delivered in a hall and not online. Please let us know the TAT, method of getting registrations, and support from our side required. Let me remind that we will only pay for paid registrations and not on unpaid registrations.