Considering a day to be 8-10 hours labor, and that your client is (for their own purposes) unwilling to pay for more than 8-10 hours of labor, don't take on the job unless you truly believe that you can regulate, tune, and voice the piano up to the playing level it really should be at for your client, within that time.   Supposing you judge that piano meets that criteria, and doesn't have any major problems, you can then prioritize your work (upright or grand) to meet your client's needs.  You know you are finished when the action is quiet, comfortable, controllable, and reliable.  Your client sits down at the instrument and playes her favorite Chopin prelude, and marvells at how easy it is for her to command every note to sound just as she wants it, and perhaps a little better.    
      If you want training in tricks of the trade, or how to get the most out of that 10 hour day, seek out the most knowlegeable people in your industry who work under the most demanding conditions, and for the most demanding clients.  Ask them if they are willing to give you hands on training.
Sincerely, 
Chris Rawson, CPT,RPT,
www.key-leveling.com

 
