Labor Day travelers are being told to get ready for high costs and heavy traffic. AAA says roundtrip airfare will cost about $750 on average, up two percent from last year. Hotel bookings have also gone up, nine-percent in the U.S. and 12-percent elsewhere. Labor Day is a week from today, and AAA says the best time to head to your destination will be Thursday morning. The worst days for travel will be Friday, Saturday, and Monday, especially after 2 pm. One tip from AAA: get your car checked out before hitting the road. Over 400-thousand drivers needed roadside assistance last year. Also, keep a spare key handy.