I have a 200 litre tank and am in the process of setting up a 700 litre tank, so have large water changes. I have a 500 litre water butt in the garden and a 300 litre storage unit in my garage, I have a motorised pump and hoses that I run from the tanks into the water butt and directly pump out of the tanks and use it to water the garden, as fish tank water is amazing for plants and it means being on a water meter I get more use of the water I pay for. Then I put clean water in the garage store (which has a heater in it), add whatever treatments and additives are required and then use the pump to move this directly back into the tanks.
In the scale of things in this hobby it wasn't expensive to set up, I get maximum use from minimum water reducing household running costs, I water the garden in the summer when everyone else has hosepipe bans. The water going into the tanks is pre-heated, so no shocks to the system for my fish, it is also very fast I don't have to carry buckets through my house, so not a drip of water gets onto my floor. Your tank is part of your home, water changes and maintenance are part of an essential routine, make it work for your home in every way it can that's my opinion.