Loft/Occupancy Code Question

[duncang]

I'm in the midst of trying to find a basis for fighting a rent increase - LL is raising the rent by more than half again ~$500. I've been on a month to month lease for about 5 years. The building changed hands and the new owner never offered lease renewal and never asked for rent increase. Now he's asking for a whopping increase and I'm wondering what, if any, options I and the other tenants might have.

I'm basing my hopes on some sort of application of the loft law although its not currently under loft law. It's a 4 unit building with a DOB occupancy code - L9 Loft Building. The actions listed on the DOB database show two certificates of occupancy with no further info except that one is dated 1931 and the second is from 1961. Finally, the general condition of the building is poor - leaky roof, peeling interior paint, minimal maintenance for last 5 years, etc.

Any ideas/information/referals would be appreciated, Thanks