@Zacharias0 I don't offer use of my washer and I've never owned a dryer in my life. I have an outdoor clothesline- when i lived in Canada i also had an indoor drying rack. And yes, I also only have one load of personal laundry a week, then a load of sheets and towels from the guest room.
What I do is when I am doing a load of wash, I'll ask a guest if there's a few small things they'd like to add to it. They have seemed to appreciate this, and takes the place of them deciding to start a wash with 2 pairs of undies, a tee shirt and a pair of socks.
A couple of guests asked for a pail and a bit of laundry soap, which I was happy to provide, and washed their stuff out like that and hung it on the line.
Most of my guests stay for at least a week. I have a 3 night minimum, and I wouldn't even offer any washing to a 3 night guest. If they arrived with a bag full of dirty clothes, that's their problem, not mine.