teekoh,
Bite the bullet and use a stop bath. Use tray stackers if you need more room in the sink. You don't need carried-over developer contaminating the prints after fixation (which would happen if you used the same water tray). True, as ROL suggests, you could use a tray of fast-running water, but then you couldn't use it for stopping development when a print after the fix was in it, plus, you'll still run the risk of dichroic fog as Ian points out above.
Four trays is really not so many... Developer, stop, fix, running water.
As for toning: the stop bath has nothing whatsoever to do with it. A non-hardening fixer is important and, if like me you transfer prints directly from the second fix to the toner, so is a non-acidic fixing bath. However, I find that Ilford Rapid Fix or Hypam is neutral enough for my purposes.
Best,
Doremus