Some leases lock in yearly increases, though, as part of auto-renewal. The last house I looked to rent included an auto-renewal clause with a fucking 5% annual increase. I noped out even before getting to the part that made me as the renter responsible for replacing the sewer if there was ever a problem with it.

first thing the current landlord did when he bought the building is raise the rent for all tenants.. despite everyone having leases--the terms and obligations of existing leases is supposed to transfer to a new owner. but they don't care, and they 100% would have raised them further (and in addition to the other increases since), had anyone pursued any sort of action against them. we have very little in terms of tenant protection laws here.