Sometimes 15 minutes is enough, and sometimes it isnt.
At my current location I am all in one. One room with all my stuff in it. I can take payment, book the next appointment, change the table and chat with a client after the session in one room. The client doesnt leave the room immedeatly after the session. They stay in the room and I re-enter and take care of rebooking and payment. Most of this I can do at the same time as chatting with a client. So, 15 minutes does work.
It is nice to have a short break between clients because the day goes by faster. However, there are times I wish I had a leeetle more time between cients. More than 3 clients with only 15 minutes inbetween gets hairy. 15 minutes leaves little time for bathroom breaks and eating on top of changing linens, rebooking, payment, soap notes, etc...
However, when I move I will have a larger area to work in. Clients will come out of the massage room after a session. Payment will happen in a different area than where the massage takes place. So, if I have a chatty client and not a lot of time after, I could be in a pickle. I figure I will do my best to have 30 minutes between clients no matter what. Worst case senario, I can tell clients to come back with me as I do my change overs. Perhaps tho, they will leave sooner since they are closer to the door.