With all due respect to HotLine, I think this is one time to A) be absolutely honest, and B ) take advantage to 'the fine print.'
In Reno, the AHJ gets nervous when you start adding plumbing to a garage. Their motive is simple: some areas have a moratorium on "mother-in-law" apartments, and once that sewer is in, it's all too easy to convert the place into an illegal residence.
If there is the slightest chance that this will be converted into a residence, I'd wire it just like a residence.
Now, as to the 'fine print:" It's not a 'bathroom' if it doesn't have a sink. If the toilet alone is in a closet, with the sink mounted anywhere else - even on the wall next to the toilet room, it's not a bathroom. There's no need for there to be any receptacle at all.
I have seen a number of workshop conversions with just this arrangement. In those cases, the 'sink' is most ofter one of those huge laundry tubs. Often there will be a tiny point-of-use water heater that supplies a trickle of hot water.
Another 'trick' is to leave the top of any closets open, letting them get their light from the general shop lighting. This might also eliminate the need for any dedicated venting or windows.
