In your situation, it’s a god send. Also being able to clean the bike before you put it in the car could save it’s interior…
I bought a dirtworker (pre nomad name change) and it was dead useful when I lived in a 1st floor flat with no access to a outside tap.
Decent amount of pressure, enough to shift mud with maybe a bit of help from a brush on really claggy stuff. A tank should be enough to clean two bikes down or one very throughly.
There are now several companies making what dirtworker/nomad started/developed.. brand-X and Mobi, for example – annoying but that’s life. I’ve used a mobi and it basically performed the same as my DW. The basic mobi (non battery version) is on offer at Wiggle at the moment so worth checking out (a bargain is a bargain after all).
Dirtworker have alway had a great reputation for after market support, and if possible I’d like to recommend there product 1st..
Check out similar thread on the dirtworker tag