The drain concern you mentioned is the one that would have kept me up at night honestly. Wheel cleaner and similar acidic detailing chemicals getting into drainage is a serious problem beyond just the floor damage. Good on you for having the kit ready and actually using it correctly because a lot of people buy them and then forget where they put them when it matters. I picked up my spill kits from Crateco which is conveniently in Ajman so no shipping drama, and they carry chemical specific kits not just the generic oil absorbent type which matters a lot for detailing workshop chemicals. The absorbent socks for perimeter control are the part that saved me from a spill spreading further than it needed to. Your instinct to add a second kit in the storage area is exactly right, that is usually where the bigger containers live anyway.