This is very helpful, thank you.
One other question I have per your comment: When you say it could be both, does that mean that it could be both within the same complaint against the landlord, or either one could be pled against the landlord? Is it one or the other if a complaint is filed, or could it be both at the same time if a complaint is filed? Thanks again.
You are welcome.
Promissory estoppel will estop the landlord from reneging on his promise to you that you have relied on - thus is more of your counter to him trying to wriggle out of the oral agreement - and yes it can be asserted on the same complaint.
Your real cause of action will be founded on breach of contract - the oral contract you entered into with him that made you a Tenant at Will - and I listed above the types of remedies you may be entitled to in court.