Cat toilet accident, no supplies!

I have a new client who has a young cat that I've been doing drop in sessions first. Few issues off the bat, the home owner was iffy about me following her round the house for the meet and greet and told me to get out a room she was in when getting the cat food. They've booked me for 30 mins a session but the house has no furniture (so no where to sit) the flooring has been ripped up, no cat toys, nothing. So I've been hesitant to stay more than 15 mins where I feed the cat, water the plants can give the cat a cuddle. Today I went and it seems like she's peed in the back corner of the living room, she has access to the outside with a litter tray outdoors? I've messaged the owner since there aren't any cleaning supplies or even a bin in the area of the house I can get to. Anyone else has similar issues with this sort of client? Not sure how to handle the drop in sessions / the accident without anything to use!