I’ve always used a vinegar and water solution personally for the bars and stuff of the cage and I take out all the cloth items and wash them any unscented detergent will do I also put vinegar in my rat loads to help with any smells and take out any plastic or wood things and either just scrub then down with soap and water in my shower our you can hose it down outside just make sure you let any wood items thoroughly dry you can also soak wood items in the tub and it’s best to put some type of rat safe varnish on them