Having done TZ, it's alot of work.
The definition of SHOP varies. To me, it's making sure that the game is 100% functional, clean with new rubber and is presentable in good working order.
If the PF is filthy then more stuff has to come off to achieve clean status.
Someone working on a pinball machine is as skilled as a mechanic. Shop mechanic rates are $75 to $125 or more an hour. Let's say the average pinball labor is worth $75 an hour for a multi-hour shop job. If it takes 4 hours, that's $300.00 If it takes more like a full day (7 to 8 hours) for TZ its more like a $600 job plus rubber, bulbs and any parts. Certainly reasonable on top of what amounts to a $6,500 to $7,500 game. It's about 10%.