I could be wrong but my understanding is that the yurts are only part of the business property. The “treatments” as they are referred to, take place in a renovated nearby barn which, presumably, has facilities like toilets which people staying in the yurts would use. Although the yurts can move, it is much harder to move the barn and there may be no alternative barn but, you know, they could tell us that.
I don’t get how Kate’s business is actually a business. She appears to be there rent free and we know from previous episodes that land in Ambridge is expensive. Is she really making a profit? As a minimum she should be required to start paying a commercial rent immediately as well as residential rent for staying in the house. This may not bring in the sort of cash they need to pay off the clean-up but it might be enough to justify a loan. It can’t hurt! It would also bring a dose of reality to Kate.