Preparation is crucial to winning your case. The most critical aspect of preparing for court is gathering relevant evidence to prove your claims. The judge will not accept assertions as being valid unless they're supported by proof.
In Landlord Tenant litigation, evidence generally boils down to paper. There is a multitude of documents that need to be collected and categorized so that evidence can be presented in a logical, coherent way, should your case actually proceed to trial. In addition to your lease, these may include letters, mail, photos, records from various government agencies, specific types of charts you may have kept, and similar papers.
Organize these records and keep then in an accordion file. Whatever is needed to make a point should be instantly accessible. If your lawyer has to take the time to do it, it will cost you extra money in legal fees.
The point of all this is that when the Court is presented with verifiable proof of every element of your argument, it goes a long way towards defeating the landlord's case.