Haven’t read all the replies but an interesting topic, lol.
I see things a lot more from your perspective than the tenants and I think you are technically right as far as the law goes.
But IMO I would avoid showings on holidays, he very well could have had plans for the evening that involved the horizontal mambo, I would make an effort if I can to avoid a showing on a day that is not convenient.
I definitely agree with the idea of showing the unit in advance and try to get a new tenant on a lease before the old one leaves. But it is a nuisance for tenants and they just need to deal with it ultimately, however if you have a obstinate tenant that is not working with you it may actually be better to wait for it to be vacant or work with them on a convenient time to do a showing. A bad tenant could tank a good prospect and you don’t want that even if it means taking a little longer to fill the unit.
You could also offer a bonus after they move out. I have offered tenants a $100 bonus after closing on a property to just help ease their cooperation with showing the building to buyers and it worked great for me.
To the average mid to lower income tenant $100 is a lot and makes a big impact.