I don’t have running water in my darkroom, so stack prints in a holding tray until I have sufficient to make trip to the bathroom, where I have an archival washer.

Not having running water in the darkroom is less of a problem than you might imagine.

However, a word of advice.

Only carry wet prints around the house.
A standard print tray is an ideal way of moving them.
Never carry trays of water/chemicals – sooner or later, it will get away from you and a complete sense of humour failure will be the inevitable consequence.