I'm in a similar position, my girlfriend's house is terraced and in a walkway. My van is in communal parking 30m away.
I've done 2 things:
1. Get your pump, controller and battery and make a pump box, with a hozelock connection for both in and out. I can drain the system, take out the pump box and put it on a sack barrow. Take out the reel (connected via pipe clips) and put on the sack barrow, on top of the pump box. Take out the pole and connect to upright of sack barrow. Take it indoors (1 trip) takes 10 mins. Stick a duvet over the tank.
2. On the odd occasion, i've been caught out and it all froze. Near me is a road that no one uses, it's nice and quiet. I drive there and park up so that the sun is directly on the back doors, open up and run out all the hose on the ground, open the doors wide up and let the sun defrost everything. It's a bit of an extreme measure, but I have done this twice and both times I was up and running in about 40 mins. You can take a cool box of very hot water to help speed up the process.
I just took a flask of tea and put my feet up for a bit!
Having said all that, you could cover everything over with a duvet and then defrost in the morning with one of these
https://www.worldofcamping.co.uk/handy-portable-gas-heater