Always check the prices of goods at similar business premises.
In some cases one can cross a street, in others its a bit farther, but always find the competitors, and compare.
The reason one does this comparison is that if the differential in the cost of an item is great, the assumption is that all the items in that premises are overpriced.
For example; Pharmacy A sold a particular item at $6.75. The same item at Pharmacy B was $2.75.
This is an enormous difference.
How did it happen? How is a product sold at this premises is nearly 3x the cost at that?
Whatever the reason, anyone hearing/reading this will not go to Pharmacy A.
Even if all their other prices are the same as Pharmacy B, just knowing that the price differential of one item is so great suggests there are other items as overpriced.