Not sure from what you describe why you would need another bill layout to accomplish this.  It seems to me that it should be as simple as turning on the previous balance and a/r transaction information on whichever bill layout you choose.  Beyond that advice very difficult to give specifics without being able to see the layouts you describe or knowing the version of Timeslips you are using.  

I thought the same thing but when both are needed it won't allow both to print on the same bill. I start with the basic bill layout, which will show the professional courtesy write off, but won't show previous payment or amount due in the "grand total" section. My Timeslips has a customizable section 1 & 2, which are both the same, and when that is added under the Expense Charges-Itemized section it will show the previous balance or payment received amount but not the professional courtesy write off.

Our office uses Timeslips 2011.

You will need to enable the professional courtesy write off in either layout you choose by opening the layout and going to the layout button up near the design tab, selecting layout options and finally "itemize client adjustments after printing slip charges".  Might be slightly different in your 2011 versus my 2014 but that is where you need to look.

It worked. I am very new to this system and the manuals/tutorials are very confusing. You saved the day!

Thank you!!