I think, by law, all job adverts should say what hours they want and what the salary is, or at least a range, or that they are flexible about the hours but give at least an idea of what combinations would be acceptable. For example, 20 hours could be 3 full days or 5 days doing 10-3. It just wastes everyone's time if you apply for a job and get offered the job and then find out you can't do the hours. I think jobs in the public sector have to make these things clear, so why not all?