Thats my half finished stool
Countersunk screws were never finished and the covering has seen better days but its still solid and not bad for a 15 year old i'm quite proud of it.
Any tradesmen is expected to supply his own tools I've never worked anywhere that was any different (electrician).
I wouldn't work anywhere I was forced to use company supplied tools that would probably be Junk.
Make sure the core is wider than 150 to allow for the ducting about 160-165 for a 150mm fan.
Just done 9 apartments for a builder and he told the corers 100mm was a nightmare.