@Josh Buchan
Not a lawyer, but as a former property manager, I went to court a handful of times on behalf of clients.
As for the big claim of rent abatement, the judge will likely disregard it. I had a tenant claim back rent like that as well. Here’s how it went:
Judge: did you pay rent each month?
Tenant: yes, but the home was in shambles, I’d like my rent back due to inhabitability.
Judge: denied. you paid rent, and in exchange you lived in a home. That’s all in the past now. Let’s move on...
Now, where you will probably lose is in regard to the security deposit. You mentioned the deposit went out to the tenant a day late. If that’s true, and the deposit went out later than the required 21 days post move out, then you’ll be giving the full deposit back. The real question is will you get penalized further? I had a deposit dispute, and when the tenant won, not only did she get back her $1000 deposit, but she was also awarded punitive damages equal to 3 times the deposit, if I recall correctly. I believe 3x is the max on punitive damages.
This is small claims court, so you can’t even utilize a lawyer. I’d make an attempt to settle ahead of court. But sometimes people are rash and stubborn.