My question involves landlord-tenant law in the State of: Massachusetts

When I was shown my current apartment 3 years ago, the realtor/property manager informed me that they would replace the carpets in the unit as the tenants had a cat. Prior to moving in I sent an email to the manager citing our discussion about replacing the carpets and requesting that they be replaced prior to move in. The manager responded that he thought he, 'had said that we would steam clean the carpets and replace if needed." He said he would have his guys take a look at the apartment and we would work something out. I responded that I would appreciate it and reiterated the amount of cat hair in the carpets. After several follow up calls to the manager, with no response, the carpets were neither cleaned or replaced.

After renewing the apt for a second year I got a dog. The lease states no pets, but several other renters in the building have pets, including the previous tenant, so I did not think it would be an issue. The property manager found out I had a dog, but offered me the chance to renew my lease for a 3rd year. The renewal offer indicated a rent increase of $190 a month. When I questioned the manager about the rent increase he informed me in an email that he, "spoke with the owner and the the increase is $190 due to the pet." Based on this response, I signed the renewal under the pretense that the rent increase served as justification of the pet and overrode any terms of the lease indicating otherwise.

After 3 years of occupancy I am moving out. The incoming tenant requested that the landlord clean the rugs. I received an email from the management company that I would have to pay to have the carpets cleaned or it would be deducted from my security deposit. When I told them that they did not clean or replace the carpets when I moved in, despite written documentation of their intent to do so, they indicated that having a pet was in violation of my lease.


Questions:

1. Do they have the right to deduct money from my security deposit to clean the carpets even though they indicated that they would do the same for me when I moved in, but never did?

2. Does having a pet even weigh into this argument given that they [1] renewed my lease despite being aware of the pet (as documented in an email); [2] know that the prior tenant had a pet who damaged the carpets (as documented in an email); and [3] have no proof that the state of the carpets is the result of my pet or the previous tenant. I however have an email documenting that there was a lot of cat hair in the carpet when I moved in and a response with their intent to clean or replace the carpet, which was never done.

3. Do the email exchanges I have serve as appropriate documentation of their acceptance of the pet and override any pet violation fees listed in the lease?