Senator B – Time spent renewing the hardy disc at the back of the diff.

Hello people. my rear hardy disk has to be renewed. I was now in the only (free) workshop here in the area and asked about the cost of the installation (without material). I was opened that everything would have to be removed (e.g. exhaust, cardan shaft and any sheet metal, front and rear would be a thorn etc.). For the change of the rear disk at least 150 euros. Here in the forum I read 30-45 minutes and he wants to wurst around it 3-4 hours. What’s right now? And how exactly do you have to proceed to change the rear disk? Please help me quickly – my only car, for which I leafed 700 euros for the HU at the same workshop 10 days ago… I already thank you in advance. Oh so… at Ebay many disks are offered at low prices. But what do they do? Where do you get a low-priced, which can withstand anything (177 HP 3.0i Kat) ?