Quick service - but parts completely overpriced

All,

The good first. Logged a call for them to come and look at my maglock on my driveway gate not working. Technician was here same day - and identified that I need a new maglock.

Returned the next day with the part - R3 500. I stopped him, and stared phoning around for the price of that part. Almost anywhere I could get it for half that price. I am very willing to pay for installation - but a 100% markup on parts that I can find retail for half the price does not make sense. Send the technician packing - I have paid the call-out fee, but I am not paying 100% markup on parts....