I am subleasing a basement apartment which has flooded and been neglected. What are my options to get damage recovery?

The basement of the place I am renting began to flood on Friday. I sent very precise updates as it spread from one room to another as I exhausted all options of taking care of it myself. Landlord has acted unconcerned, careless, and arrogant. I demonstrated extreme patience and understanding and trust with his promises to take care of it. However it seems like the very bottom priority. You can see a copious amount of mold spots on the walls at this point. No progress has been made, in fact any attempt has caused more damage. There is no written and signed lease it was a mutual sublease with main tenant. Landlord has stated to give him a figure to conver damage but I am positive the cost of hiring a professional straight off the bat would be cheaper than the compensation of damage caused. There is no written contact however there are email exchanges and text. I'm so distraught. What are my best options?