@Andye0 I would not recommend using AirBnB for any stay longer than 28 days, or whatever time frame would throw the guests into a (by law) long term rental situation with extended eviction rules. AirBnB does not guarantee payment after the first month. If you want to have longer stays, seek the advice of a realtor and have an ironclad contract that is signed by both you and the guest (that includes payment information) and protect yourself.
When I rent long term (and I do have properties that I rent for 3-6 months) the guest is informed that there will be a cleaning/property check every two weeks, that it is conducted by either myself or a named housekeeper, and that the fee will be X dollars each time. This is in the contract. I would never attempt to do this through AirBnB.