As a provider, I wait until the client says "yes" to a
date and time before the appointment is confirmed. If he never says yes to a date and time, the appointment was never confirmed.
For clients, I recommend waiting for the provider to say "yes" to a
date and time before thinking the appointment is confirmed. If she never says yes to a date and time, the appointment was never confirmed.
Both saying yes to a date and time means the appointment is confirmed.
That's it.
It sucks when a client and provider end up....
General location. If you are only willing to drive so far or if certain information is needed to determine the points above, then this should be discussed before giving the "yes." But other than that, I don't think a location is required for two people to know whether or not their date is on.
Last minute confirmation. I don't consider confirming last minute as a step required in determining whether or not a date was confirmed. Confirming last minute is a precautionary measure to ensure the other person hasn't forgotten about an already confirmed date. In other words, a last minute confirmation is an extra step a person can take to double check that nothing has come up that would interfere with their already confirmed date. I personally don't need follow up confirmations, I just ask to be notified if our date needs moved.
Instructions on how to proceed. I don't need this to determine if my date is really really really confirmed. If both parties assume "yes" to a date and time means appointment confirmed, then discussing a meeting location would be the natural progression.
Canceling. I think a date can be confirmed without either party having discussed the proper way to cancel. It is polite to always provide as much notice as possible when an appointment needs to be cancelled, but I'm not sure I would need to know the best way to cancel in order to determine whether or not my appointment is confirmed.
Some things can be very helpful/good to know in advance.
If the answers to certain questions may result in a yes becoming a no, then those are the questions that should be asked before the yes is ever given.