Edenvale Gearbox and diff out to rob and *****

I phoned for a qoute to have the diff bearings in my 2010 volvo xc60 replaced. I was told it would be R3300 labour plus parts. Parts would be around R4500. I booked the car in and within 2 hours of dropping the car I was sent a qoute of R21000. Not a detailed qoute just one figure of R21000. I expected a breakdown like all other places. I argued about the price then they came down to R14000. That's a big drop within 5 minutes. I still argued that it wasn't the telephonic quote I got. I decided to fetch t he car. To my surprise they never stripped the diff off the car to assess it. How did they come up with a R21000 quote. I took the car to Delport diff and gearbox in Booysens and they done the job for R7480.00 car driving perfectly now. Edenvale Gearbox and diff is definitely out to rob and ***** from customers.