Stipulations in a lease vs. law when breaking a lease
I'm breaking a lease with my landlord 6 months in (I'm moving out of the country). I've found someone to take over the lease immediately upon my departure. I informed my landlord 5 weeks prior to the point where I'd be breaking the lease. The landlord has (three weeks later) informed me that they will charge me a $400 paint fee and $100 service/processing fee. This is stipulated in the lease, although I asked them to forgo, since there has been minimal wear and tear on the apartment (i.e. it doesn't need to be painted) and I found another tenant. They're not budging.
Although it's in the lease, is it legal for them to charge "paint fees" and "processing fees" as a matter of course? They've never once looked at the apartment. In fact, I've never met or spoken to the landlord. All correspondences have been conducted through the superintendent.