If the landlord accepted any rent from you for the period after your lease ended, you are now a month-to-month tenant. Your landlord cannot just throw you out. He will have to send you a 30 day notice of termination. That notice must state that your tenancy ends as of the last day of a month, at least 30 days after you receive a copy of the notice. If the landlord served you a termination notice today it would have to terminate your tenancy on October 31 because there are less than 30 days before the end of the current month.
If you did not move out after the termination date, the landlord would have to start a case against you, called a holdover proceeding, to recover possession of the apartment.
Since your landlord allowed you to sublet part of the apartment o his daughter as one of the terms and conditions of your original tenancy, that right carries over into the month-to-month tenancy. Your landlord cannot now come and claim you are not permitted to sublet or charge his daughter. You are entitled to charge her $800.00 for the current month.
Your landlord, however, can increase the rent. If your apartment is not rent stabilized there is no restriction on the amount of any increase. If your landlord sued you for the rent, a court might or might not find that he is entitled to the increase.
The above constitutes general information only and should not be considered legal advice.
If your lease ended in July you are a holdover and your landlord can evict you by following the legal procedure. He can't just throw you out.
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