Builders Warehouse - overcharges!

I wanted to get a 5 litre tin of Micatex colour Lions Den. On Googling this I found only Builders Warehouse, Table View, and Buco Hardware, Montague Gardens, could supply this. I emailed Buco and got a quote of R379-99 from Stuart Thornhill at Buco. As I was closer to Builders, I drove there and was quoted in excess of R600. I almost laughed in the assistant's face. I then drove to Buco in Montague Gardens, and saw Stuart Thornhill - who incidentally was the most helpful and knowledgeable person, I have ever known. Within 10 minutes I had the paint and was on my way home. How can Builders possibly justify a price of more than 50% above Buco. I would advise shoppers to shop around before buying anything from Builders - NO STARS FOR THEM!.