Is there any general consensus on how long to wait for a response to an appointment request - particularly, after a fresh ad is posted?

Unless you have actually booked an appointment with her, you owe her nothing until you do so.

If I realllllly want to see them, I respond right away or as soon as I see it. But doesn't mean they will see me that day. I have a life and I have to plan my day. Lol

Agreed 10000%

I will have a personal assistant, someone whom I literally trust with my life (because she does my verification) and who also has a presence in the TER community.  She is a very reputable provider, who is a Ms. TER, and who also owns and manages a verification service for many TER providers across the USA.  

Why not put several inquiries out at once and see who gets back to you, or space them a few hours apart to umpteenth hours apart; that is, the duration of time is up to what you feel comfortable by waiting for a reply. But look, it’s an inquiry and not an appointment; otherwise, once you agree on making an appointment, go the extra inquiry and ask the provider if she has a cancellation notice (within reason) in case you can’t make it. (You might do this if you prefer another choice, like the special advertised that did not get back to you at first; thus allowing some time for a possible change of mind.).

...I send a second email inquiring if they got the first one. If it's radio silence after that I write them off permanently and move on to someone else.

once I have booked with someone, I send another message to the ones that didn't reply telling them someone else (sometimes I will name the provider that I have booked with) has responded and I have booked, so please disregard my inquiry.  I do this so that they will know they missed an appointment by not getting back to me in a timely manner.  Perhaps it will be a learning experience for them for next time.  I usually book one to three days in advance, and only make an inquiry to a current ad, so there is no excuse to leave me hanging.

If you are arranging for an immediate or very soon appointment, then obviously your schedule dictates the time to wait.  But if you are wondering how long to wait, it sort of implies you have some time.  In that case waiting only an hour seems a bit rushed.  She may be with a client.  I like to book in advance, so I'd wait 24-48 hours

I am preparing for, on my way to or in an appoitment my phone is always in Do not disturb. I think would be disrespectful answering or watching my phone when I am with a client.  I put the playlist and let the night go. Sometimes clients ask for extended  time, it could be an a hour a couple of ours or an overnight, but I leave my auto reply when busy or out of town so people know that I am not available and they do not feel ignored. After that I try to answer my emails/ texts within 24 hours.

If it's for something the next day or two, I try to give them about two hours.

If it is sent between 7 am and 10 p, I typically am able to respond to it within an hour or two. Probably the only time it would take me longer is if I was inundated with emails or if I was traveling (driving, flying a long distance).

Sometimes if I'm at my other day job I can't always check emails every hour - or if I'm already in a multi hour date with someone I wouldn't. If you miss out its bad luck sometimes not because we're ignoring your request.

As a provider i would advise you to reachout to a few ladies your interested in.Just inquire about their donations and availability,if i were you id wait about an hour bc her time may be consumed with another guest..or she may not be "on duty" at the time.If an hr pasts and you still do not hear back ,then call and leave a message.If you do not hear back from woman of your choice,then i would just move on.

I usually try and book at least 2-3 weeks in advance so I give them a week to respond. If no response after a week, I'll send a follow up email, just in case my email ended up in spam. In my original email, I'll have my TERID, full name, city I live, phone number and provider info just so I can easily be screened. If they don't get back to me in a day after my followup, then on to the next one

I have no need to do that. If I send an inquiry at lets say 9 AM and I haven't heard anything by let's say 10, I may very well start looking for someone else and let's say by 11 I have found someone and booked with her for a 4 PM appointment, Now at noon woman number one gets back to me. No problem, I simply tell her plans have changed for this afternoon (no need to tell her I made an appointment with another woman) and how does tomorrow look? See, no hard feelings on either end and I have just taken care of finding tomorrows date. lol

about three years ago for not allowing a provider three or so days  to respond to my request for a meeting. What changed?

Gawd, I love your way with words, indeed I do!  

he wants to see you and for the same length of time, then he can send reference information in order to get verified and the appointment finalized. He knows his search is over.

other words, if I'm trying for a date next week I will wait about 24-48 hours for a response. If I'm trying to get a date for tomorrow night, then my wait time is much shorter, say 1-2 hours.

I use the shotgun approach-contact all providers I am interested in (usually no more than 3)-and first response gets the date.  After all, I'm sure the ladies have better things to do, like be in the middle of an appointment, than to sit by the phone waiting on me to call.  When all else fails and I really really have to have it, I will take a chance on an agency.

britches?  we don't need no stinking britches....

Is your name Patty?

We all know it usually means she hasn't finished with her previous client, but why rub the clients nose in it by stating "sorry,  but she is still fucking someone else" lol

but it is funny how opinions change over time. It's like the topic of "envelopes" Years ago the manginas and BSC hookers wanted to tar and feather me because I flat out refused to use a silly envelope, I was called everything from "disrespectful" to "dangerous" for my opinion. Fast forward to today, and most people don't think it's any big deal.

I'd have to go back and see what your comments were.

If you are "booked" with a provider, you owe her a certain benefit of the doubt that you don't incur when simply making an "inquiry"  

I try to be quick but refuse to get a smart phone(I don't need my emails to be potentially in the air and intercept possible or monitored by my cell Co).  I am wired on my laptop even and have to be online to respond to email.  Don't have text, but I do answer my phone....

I never booked with the second provider. We had only talked general times of the month, and nothing specific.

I really appreciate it when someone gives me 24 hrs to respond. Often I answer immediately but sometimes if I am out and about with my family or civvie friends I don't prefer to risk opening my phone to check emails. Sometimes I might excuse myself and check real quick but if I can the date is not for the same day then I prefer to respond later. 24 hrs gives me time to do screening in private. If in the process of screening I find out the client has messaged a ton of ladies for the same appt time then I don't bother with the booking because I know they might cancel on me if someone else answers their request.