Disgruntled tenant turning hostile

[Misha Gounder]

My ex tenants are suing me twice the amount of retained security deposit for damages. I had sent them a list of itemized deductions (hardwood floor damages $1600, utilities - water, sewer, trash, and electricity $370, and $95 cleaning fees) and remaining security deposit $3600 check within 15 days. In addition, I also sent a letter describing the damages, & photos of evidence. Yet they mailed me a demand letter that they wanted their entire deposit back. In response to that letter, I sent a certified mail letter describing in detail the nature of repairs, and reasoning for all deductions. I have now received court summons in small claims court for twice the amount of their initial demand!

Then I received a letter from the City notifying me of a home inspection! 

Here are a few questions I have:
1) Why did the tenants NOT acknowledge my certified mail letter with detailed reasoning of deductions? They have filed stating I did not provide any reason for deducting their money!
2) What evidence can these tenants have to prove they didnt cause these damages? or that they dont have to pay for utilities - water, electricity they used, or $95 cleaning fee? I had sent them a certified mail showing a move-in condition checklist signed by them stating no wood floor damages, photos of damages when they moved out, and local floor expert recommendations that this is NOT normal wear and tear. I am trying to understand what makes these tenants think they can get away with this?

It seems to me these tenants are very hostile, and they've demanded they want their twice their entire security deposit back no matter what damages, cleaning or utilities they used when they were staying in my home. They have also become hostile and complained to the City about my home. What do you suggest I tell the judge in 15 min?

I've had many tenants in many properties over several yrs, & no issues

Thanks much!!