I have been filling tear troughs successfully for over a decade, and have never needed 4cc of any filler. As well, the cost will be based on various factors, including the expertise of your injector. The tear trough area is by far the hardest and most complex to inject, so I wouldn't go for "a deal" at the expense of your health & safety & appearance. Best to have a filler/tear trough expert, e.g. a dermatologist, to assess you for optimal results and safety, and an honest quote for cost and what is truly needed in your case.
