I do it by right clicking on the client in Homebase, then selecting Rename. I usually don't need to change the path, so I just enter the new file name, but since the current path is showing, I would think that you could change that as well.
Even if you can change path and file name, why would you want to. Users of PS cause a lot of problems for themselves by changing defaults. Have been using PS for 20+ years, and I neve had the need to change default file locations. I do change file names occasional (amended, filing status change etc.)