Security Deposit: TV Wall Mount Installation

[Hae Sun Yi]

Hi

When I did a moving out walkthrough with my tenants, I've noticed that they took down the TV wall mount that I left when they moved in two years ago. They said it didn't fit their big TV so they installed a new one and they took it with them and left mine in the basement uninstalled. So the wall is empty now.   

I thought I can ask them that I need to deduct the cost of installation since my new tenants want their TV wall mounted. I checked the contract and it states in the section of "Alteration"-No antenna or other equipment (not specific TV mount though)

1. Is it the thing I could deduct from their deposit since they didn't ask permission to replace? 

2. I didn't bring that up at the walkthrough but can I still claim it since I have 30 days deposit return policy and they moved out on 8/28?

3. Can you give me advice on how I could access this issue briefly? Should I hire a professional TV mount installer and send them a quote?

They were my first tenants and I am still confused with what to ask or whatnot and how..Thank you so much for your input in advance.