Washing depends on RC paper vs. fiber. RC washes pretty quickly, fiber you 100% should HCA (or just buy sodium sulphite by the pound), and there's really no way I'd print fiber without Residual Hypo Test (RHT), one bottle lasts years and it will save a lot of water and washing time. Either way, a good bet is have a way to give the prints a solid rinse, and then put them in a holding tray of water. take your keepers inside and wash 'em in the bathtub.
With some tubs, you can rig up a PVC pipe over the drain - the idea is to get the draining up several inches so the tub will hold some water and it overflows over the pipe into the drain. the tub's overflow drain will work, but that means you're filling the tub up. You can also do things like rig a couple boards across the tub to hold a large tray and let the shower dribble into it. In the US, most showers are a 1/2" NPT thread, so you can very quickly unscrew the shower head and screw on a barb fitting with something like 1/2" flexible poly hose, run the hose down to the tray and clip it to the side. When you're done, take the hose + fitting off and coil it up and stash it in a cupboard, and stick the shower head back on - you'd want an adjustable wrench handy for that, but it's actually very quick and works well.