Do I need to provide a toilet for my clients?

Naturally, this would be great and you could charge more for your place. However, if this option is not on your property, it's not a problem, it can be solved in several ways:

1. Caravans and motorhomes have a chemical toilet inside so they don't need anything at all. The tank inside lasts about 3–5 days depending on the intensity of use. Usually, they won't be on your property any longer. If so, they must empty this tank. Of course, it is forbidden to empty it on your property. Caravanners know how to proceed, i.e. they usually use e.g. a petrol station.

2. If you allow accommodation in a tent on your property, it would be desirable for you to instruct guests how to proceed (and this should be stated in the description). There are more possibilities. Examples:
- make an arrangement with a nearby restaurant (they will certainly meet your needs, especially if they can get a customer)
- make an arrangement with your neighbours
- think about installing cheap and simple eco-friendly toilets not requiring any connection
https://cs.wikipedia.org/wiki/P%C5%99enosn%C3%A1_toaleta
https://www.qrshop.cz/prenosne-toalety/
Yes, it means extra worries and extra work, but if you provide this to guests, you can get paid for it.