Guessing its not someone whos done one before. Even for me it was a 30min job. Would be max 60 minutes going very carefully which is what say 80+gst unless its a dealer at $120+gst or whatever. Cant imagine that was a dealer quote tho....
Changing diff oil in a road car every 15000km is nonsensical. It's not smart to change oil heaps sooner than required it just short changes your pocket. Providing you use the correct oil, stick to the oem intervals there is nothing to be gained shortening the interval.
Cheap chinese taps are S***. Decent ones like turbosmart are bloody good.
Both are nothing like a proper closed loop system which link provide where the turbo comes on quicker as the gates kept shut till its required to open.
There's no debate that a simple line from boost source to gate doesnt work just that its far from optimal.
A wastegate external or internal is not an on/off switch. That's what the boost controller does. Stops the gate from opening until it meets target.
If its so great with no real boost control why bother wiring up a solenoid for the link?
Without a decent boost controller electronic or manual the gate will crack open early bleeding off pressure better spent spooling the turbo. A 1 bar spring doesnt open at 1 bar, it opens progressively finishing at 1 bar.
Do you have a boost gauge and is all of the stock boost control in place?
Plugs been changed lately? No codes?
Should be running 98 fuel or it will be knocking its tits off.