Sorry, but I've got to ask ...
Why is it that people don't hold the workshops to their quotes? If they quote you, then want more when they're doing the work, it comes out of their pocket. Why do people readily throw cash away without question. I have never allowed any shop to get more out of me above the written quote.
A mate of mine took his v-twin sports bike to a Murray Bridge workshop for some minor mods, and they blew up his engine! He nags them for months for his bike back fixed, and they finally tell him its ready 3 months on ... with a bill for nearly $5500!!!!! $1K over the quote for the mods and an extra $3K or so for the rebuild on the engine ... which they blew up! And he was going to pay them because they were holding his bike to ransom. I gave my mate some advice and helped him take the matter to the ACCU and Court.
But he was just going to surrender and hand over the cash.
I've even had my cars and bikes serviced at the dealer at a fixed quote. Then when I go pick it up, they throw in extras for dirty filter or some other small item etc. If its not on the written quote and I didn't authorise it (especially if its not required for that particular service interval), I won't pay for it. I even had one shop charge me for a replacement stock air filter on my TLR bike. I hit the roof because they threw out a $130 washable BMC filter. They ended up replacing it with a new BMC filter.