If you go for a hotel, say so from the start and check that the ad accepts that format. After that the coordination is fairly standard: you book the room, send the room number by message once you are inside and let her know if anything shifts. There is no need to go down and wait or announce anything at reception.
The first message is best sent ahead of time and with everything on the table: day, hour, duration, address or name of the hotel. Nobody confirms blind here, because coming out to the neighborhood means organizing the rest of the day around that date. The more complete your message, the faster the reply arrives.
Given the sort of clientele in the area, social company carries more weight than in other neighborhoods: dinners, events, outings lasting several hours where the meeting is only part of the plan. There is also demand for long dates and for massages. Each of the escorts covering the area states what she accepts, and it is worth reading the whole thing.
One point that matters more in Carrasco than elsewhere is how the date ends. Agree the duration in advance and stick to it, because stretching it throws off the agenda of someone who came from far away. And if you are going to cancel, do it with as much notice as possible: here a last-minute cancellation means a wasted trip, not simply one slot less.