PBA: I dunno. I’ve seen leases with the clause that as long as there is 24-hour notice, he can show the apartment during any daytime hours during the final month/2 months of the lease. Hopefully he’ll respect your wishes re Shabbos/the birthday party, but depending on the lease it could very well be his right.
There are very few jurisdictions that don’t regulate residential leases, so most provisions of your lease are subject to overriding law anyway.
I would definitely, as a tenant, read that as including a reasonability clause. For example, you can’t set up shop in my apartment every day, all day, for the last two months. No contract can possibly include every eventuality, and I can’t imagine any court would read that literally.