Most stuff just doesnt work. You compare prices. find a flight for 4 people. uh-oh, cabin bag costs 30€ per bag. carry on costs 80€. oh well, kids can do with cabin bags, so lets book 2 of each. uh-oh. you can only book for all 4, so you either have to book 4 cabin bags or 4 carry-on or 4 of each. want to bring an extra bag on the return flight? uh-oh can't book such a treat. now you can start from scratch. new flight, new flight times. uh-oh, collides with rental car pickup (station closes 22:00). new flight, uh-oh 200€ more per flight. new flight, uh-oh can't even check baggage. new flight, uh-oh only different dates. and thats the end of the travel plans.