There are two ways, either you do a contract with every single hotel as said by our friends above. But this will take a lot of time feeding hotel contents, put contracts at place and other similar jobs. This may be a huge investment. The other way is to go with API based site like WordPress Real Time Hotel Booking Theme, WordPress Hotel Booking Theme.

Now as you will have a Website covering almost the globe. Take these hotels as placeholders and keep filling the hotels of your own contracts through Admin. Pick the major cities in your country first following with the rest of the other cities/destinations.

As the rates that you will receive from hotels will be comparatively less to the ones pulled via API. You should promote the hotels that come under your contracting. Collect the payments with the margins and perform the bookings at your end. The more bookings you have, the better rates you receive from hotels and ultimately it again helps you in selling.

Once you reach a certain stage, you can partner with companies in other countries doing the same kind of business.

Hope this gives you an idea.

Cheers!

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