Greetings Arco,

The cost may NOT be your landlord's responsibility. Look at your
lease. If the window is only a few years old it is likely damaged, not
worn out. Damages are often the responsibility of the tenant (even if
someone else throws a rock through your window.) The landlord gets the
money from the tenant. The tenant is then in turn responsible for
collecting the money from the responsible party. It all depends on
your lease.

Hope this helps,
William