With credence goods consumers cannot judge the quality they receive compared to the quality they need. The needed quality can only be observed by an expert seller who may exploit the information asymmetry by cheating. In recent years various contributions have analyzed the credence goods problem...

Most of us need the services of an expert when our apartment's heating or our washing machine breaks down, or when our car starts to make strange noises. And for most of us commissioning an expert to solve the problem causes concern. This concern does not disappear even after repair and payment...