@Caroline1064 depending on your market the 4 weeks of 4 days per week may well make sense. Assuming it is Monday through Friday that would then give you the 3 days of each weekend to find another guest.
If you want to incentivise this guest you can easily discount the 4 days of each week.
Of course if your market is one where its easy to fill weeknights but not weekends you shouldn't agree to a discount.