I know this much, if your barber told you $20, and you argued it was only worth $10, and he agreed to give you a $10 haircut, you wouldn’t like the results.
You won’t like the results of a cheap drill job either.
If you go to the hospital for heart surgery, do you haggle over the price and look for someone who will do it cheaper, or do you pony up for the good guy who knows his shit?
Point is, the price is the price. He can ask what he wants, and you can pay it or not.
You asked if it was possible to drill the holes yourself, so I linked a YouTube video of someone doing just that. Now you know how it can be done, so either go pay the man what he’s asking, or drill it yourself and save the money.
Discount heart surgery usually doesn’t work out too well............