The fourth-generation Mercedes-Benz C-Class (W205 for the sedan, S205 for the wagon, C205 for the coupe, A205 for the convertible) marked a major stylistic and technological break from its predecessor. Often dubbed the 'mini S-Class' upon its release, it introduced an unprecedented level of perceived finish quality in its category, although early model years suffered from some assembly flaws (rattles). The 2018 facelift (Phase 2) corrected most of the initial defects, introduced new, more efficient engines (OM654 diesel and M264 gasoline families with 48V mild hybridization), and modernized the infotainment.
The Mercedes C-Class W205 is an extremely attractive premium sedan, but its reliability is mixed, particularly on Phase 1 models (2014-2017). NOx sensor issues on diesels and early problems with M274 gasoline engines warrant caution. We strongly recommend targeting a facelifted model (Phase 2, from mid-2018 onwards). Not only is the interior build quality much better, but the new generations of engines (OM654 and M264) are generally more reliable, despite some quirks with the 48V mild hybridization. A service history from the official network or a recognized independent specialist is absolutely crucial before any purchase.