Am pretty sure he's right. I rent out my house, and it is very illegal for the landlord to record video inside the house (or even of the driveway). You are infringing the privacy of your tenants and is a huge no-no.

Yeah, if you accidentally recorded families walking through their homes unclothed, this could land a landlord in jail.

The contract terms could very well have actually had a meaning that included filming inside the apartment. The existence of other laws overriding the contract isn't actually the same thing as the contract not having that invasive meaning.