What has worked for me is to have 3 seperate benches, each for a
seperate function. The first bench for your "clean" construction work
(soldering, final assembly and small parts work), with soldering iron,
parts bins, etc. A second bench for your "dirty" work (metal cutting,
drilling, plastic cutting, etc.) with big tools, drill press, etc. A
third bench is the "test bench" with all your meters, scope, etc for
doing testing and adjustment of your bot. Bench size depends on the
space available, but shelves and such reduce the bench size needed.
With this setup, your messy stuff doesn't get in your clean areas, and
you just unhook a part of the bot and carry it to the clean or dirty
bench for modification, instead of having to clean off the bench and
move everything before you can get at your tools.
And face it, you will occasionally use these tools for lamp repairs
and other mundane tasks, and it's nice to have the "assembly" benches
always available without having to move the robot being tested.