13. BMW 745i E65
The BMW 7 Series was always considered a prestigious luxury sedan filled with power and comfort. However, the 2002 to 2008 model was dangerously close to ruining its reputation since it was notoriously prone to braking, electrical failure, and engine problems (Via BMW Blog).
The E65 generation had a specific and controversial design. Also, it was often called ugly. However, BMW is filled with the latest technology, electric systems, and numerous innovative features. This is the reason why it was problematic, and customers reported many problems. If you are offered a 2002 to 2008 model, walk away from the deal.