I think there may be some confusion between us here.
I am not sure why you are thinking you have to schedule the time in a quote? You don’t have to. You might want to so that when you generate a workorder from the quote, the scheduled users are already entered, but by all means, you do not have to enter scheduled users in the quote.
Do try it - don’t enter scheduled users. Just enter the labor and parts you want to quote on.
If you still have a question about this, please do provide more details as I must be missing something from you.