Tenant Security Deposit Issue

[Bob Young]

Hello, I am in NJ and own a condo rental. Had a terrible tenant for a year that finally moved out. Chronic late payments, bounced checks etc. however ultimately I was made whole and got rent for each month. Prior to lease maturity they request a 1 month extension which I agreed to and they were to allow me to show the property per our lease agreement. 

They became very unresponsive and I have documentation on all attempts by myself and realtor trying to get in the property. It was not until the 13th of the month I got a text notifying me they shattered a window, plus other damages. In the same message they stated that is why they were not responding. Long story short, I worked with my realtor and he finally was able to enter the property on the 19th (they kept delaying) and set in motion the repairs. He said the property was a mess and there was also significant damage to my hardwood floors which need full replacement in sections (tenant paid for that prior to moving). At this time it was not in a condition to show any potential prospects. 

Fast forward, they move out end of month and we make repairs. I had $3,000 in security deposit. Repairs were $780. Monthly rent was $2,000 and they got the balance in returned security deposit. I feel obviously that $2,000 should still be kept as I lost an entire month of opportunity to market the property and surely would have had a new tenant lined up. I received a notice from the former tenant requesting the money $2,000 returned and threat to sue. 

NJ not being too landlord friendly - I've come to learn, from an attorney, that the $2,000 in rent I cannot keep from the security deposit as it is "future rents." My only recourse is to take them to small claims court. 

I'd like to get feedback from others who have experienced this and if it's best just to suck it up and move on, or if there is legitimate chance of me be successful in court? I have a tremendous amount of documentation and every single text message conversation we had showing how accommodating as a landlord I was and essentially proving with their own words they are lying in the letter they sent to me being unresponsive and never asking them to show the property etc. But does that even matter?

Appreciate your time in reading this and look forward to feedback.