if your still bonking away 20 mins after the appointment then i would suggest that you need to manage the time properly that you spend with the guys so .....
Get an ipod or an mp3
do some playlists ie 30 mins approx (7 songs) 45 mins 10 songs / 1 hr 13 songs
in fact what i do is use the 30 mins then add a few from the other playlist so that i know at any given time where i am and how long of the appointment i have left with each client
Towards the end of the last 2 3 songs on an hour appointment you know you will have approx 10 - 15 mins left of your appointment so you can begin to wind it down a bit
Things that i might say to a client when bringing it to the end of the appointment is would you like a shower, ( if they say yes then just say ok ill grab some towels and put the shower on for you ( if they say no then say ok im just taking this (used tissues /condoms drinks downstairs ill let you get dressed ( dont put a bin in the room as its a great excuse to nip out and do this at the end of the appointment)
When they are in the shower dont stay in the room go into the lounge or kitchen and give them time to shower and get dressed on their own and just return in a few minutes when you think they are almost dressed and then walk them to the door
Or you can say what have you got planned for the rest of the day ( this allows you to reply with anwsers like other bookings, shops , meeting friends, off to church
watching jeremy kyle lol ect in a totally natural way,
also have some sort of routine so that you know where you are as such, it dosnt need to be clinical, but it needs to cover the majority of stuff that you do
while im not a clock watcher, its very very rare that i go over the alloted time with personal services i dont mind if im chatting afterwards as it my choice to do that but i dont go over the time with regard to sex and personal services as thats what they have paid for i make sure that they get the full time with regards