OK, My time to spout off, and it will probably go against the popular opinions. This is MY opinion and not necessarily the answer to YOUR problems.
In my business, the business is run the way I/ME/MINE decides to run it. If the guy doesn't want to build YOUR engine in HIS shop with YOUR parts, I don't have a problem with that. Even if you have a certain type of "relationship" with the shop owner, I still wouldn't "expect" him to change or modify the way business is done.
When I was wrenching for a living, I had way too many customers want to rerun the parts I wanted to replace, get parts for my cost, and give me advice that their buddie's cousin's sister's brother-inlaw gave him, and the brother-inlaw was a bartender with a psych degree. And it's always about saving YOU money at MY expense.
If something goes wrong when I use or reuse your parts, it's not the warranty I am worried about as much as my reputation. It doesn't matter whether or not I warranty my work with or without your parts, if it fails, it makes me look like a crappy mechanic. It's hard enough to "try" to be perfect without adding the customers variables to the mix.
The machinist probably had some bad experiences in the past using someone elses parts and doesn't want the hassle of trying to argue with you about who's parts failed, and ruined the rest of the job that you want him to fix for free and stand behind. The shop owner is trying to use his "best" judgment based on his prior experiences.
98% of the customers are honest and fair. It's that 2% that really burn a shop owners butt. To be fair to the customers, there are crappy businesses out there that give the rest a black eye. Many do have a hard time fessing up to their mistakes.
I didn't mind seeing the same vehicle again in the shop, but my goal was to never see the same vehicle in the shop for the same work I had already done. I don't think anyone likes to redo the same job over. I would rather explain why I spent another $50-100 of YOUR money on the job so it could be done "right", than to explain why MY job failed because I didn't play it smart.
A price estimate should be within 20% (plus or minus) of the final cost. But that can change when you come in and want something else done (while they are at it). If the estimate is $1000, there should be no suprise if the final bill is $1050-1200 (remember to calculate taxes too).
If you don't like the way the guy does his business, take it to your buddie's cousin's sister's brother-inlaw with the psych degree and have a drink with him when your crying over the results.
