Yes. MORE than once. Though some CL sellers won't bother to spring the new price on you, until AFTER you arrive, cash in hand (and contrary to some of the posts here, it makes absolutely NO difference if you arrive within the hour, because they never had any intention of selling at the posted price. Some of them will also berate you for walking away.)

Of course the great majority of sellers are not like that - but you just have to accept that they are out there. IMO, they are the ONLY downside to the hobby.
- A