The only critical moment where the rinse water really should be around 100degF/38degC is after the first developer. (If you are planning on doing 3step E6, there are two intermediate rinsing steps.) Of course it's good to do the final rinse in warm water as well, but it doesn't need to be spot on 100deg.
But this machine isn't that big or heavy, so you can quite easily carry it to your kitchen or bathroom and then drain it and take it away when you are finished. My ATL1000 isn't stationary, so I do something like this all the time (even though I put it in my darkroom and hook it up to my temp. controlled watertap, I need the space for other things when not processing film with the ATL). Just see to that you find a flat surface to get it leveled and also near a drain.
Btw, I get excellent results with my ATL1000, it's a nice machine. I also have a CPP2 for b/w work, where I like to be a bit more in control, but with the CPP2 I miss the automation, i.e. just press start and wait half an hour or so for the beep.
//Björn