Unacceptable paid repair quote

I tried to get a Nikon lens repaired. The lens lost one of the retaining *****s on the Zoom ring which is a well known problem with this Nikon lens. I was forced to pay R400 before the lens would even be inspected. Having no choice i paid. After days i received a quote for more than R12000 for the repair! Needless to say i did not except that ridiculous charge. In desperation i did some research and found a Youtube video on the exact issue. 20 minutes later i fixed the zoom ring issue myself and the lens has been as good as new ever since. Seems like this supplier are making their profits from inspection payments and then handing out such ridiculous quotes that nobody will except. That is a win-win business model right there as they are the sole distributor of Nikon camera equipment in South Africa.