If the same hotel comes from two different suppliers, will my customer see it listed twice?

No, in most cases your customer should see one entry for the hotel with the different rates grouped underneath it. Portals match the properties coming in from each supplier against a single list of hotels, so the same building is recognised as one property even when three or four suppliers are selling rooms in it. Your customer then picks a room and a rate, and the booking goes quietly to whichever supplier gave that rate.

The matching is only as good as the details the suppliers send. Most of them send a name, an address and a position on the map, and that is usually enough. Trouble comes with properties that have changed brand recently, with small guest houses that share a name with others in the same town, and with new hotels a supplier has only just added, because a property that has not been matched yet can appear on its own line next to the one it belongs to.

If you do spot the same hotel twice on your portal, it is worth reporting rather than ignoring, since these matches can be corrected so that the property joins the right group for everyone searching after that. It is also why the number of hotels a supplier claims to have and the number your search shows will rarely be the same figure.

The next thing to do is search a city you know well and look for any property showing up on two lines, then pass those on so the mapping can be tidied up.