Also note we have updated TimeTracker but it's not on the store yet... will hopefully be there today. This also lets you add your rates and records the time you spend on all your work. Then you can report on this in terms of dollars due!
Have you tried using any of the apps from the app store? For example... Qualitivity can do this for you and it also allows you to set rates so you create a report for the time spent on specific tasks.
There is also the TimeTracker but I didn't see a lot of enthusiasm for this to be updated to 2017 so it currently only supports 2014. Would that be a better option?