If this 3rd season is like the 1st two, then they will almost 100% travel through the States. They travel to about 6 or 7 pitstops on their route with no plane travel.
The first season, the starting destination was London England to Singapore. They had 5 or 6 pitstops in between in between, the only money they were given what worked out to what 2 plane tickets from London to Singapore would cost. At the start of each leg they were given a guide book that had places set up where they could earn money, some places had room and board included.