Can Landlord Use Last Month's Rent towards Damages?

[Heather O.]

QUESTION: CAN I, LANDLORD, WITHHOLD THE LAST MONTH'S RENT ALONG WITH DAMAGE DEPOSIT FOR DAMAGES IN FLORIDA?

I searched previous discussions and couldn't find this question, somehow.

The specific story if it matters:

Purchased property with Tenant in place, the first thing he said when we met is that he's moving.  I was glad to hear it because the house was severely under-rented and this tenant was clearly incapable of caring for a property, covered in greasy dusty cobwebs and terrible odor.

I met with Tenant twice, performing walk-through inspections both times. The tenant complained that thousands of dollars in work was needed. He admitted to never cleaning once in 9 years.

He refused to sign renewal that was offered to him 8 months earlier, so I served him with a letter stating we would not be renewing, he handed back a letter saying that he would leave even sooner than that, demanding money up front to walk.  I refused.  He ignored me completely.  So I sent him a new lease at market price, since it seemed he resolved to stay.  Luckily, we learned that he did in fact leave and there was a "purposely broken pipe in the kitchen" when I walked in, my plumber's words.  

Tenant wrote to the management company / us, "I was advised by Heather Olson that I would receive my deposit money back promptly as soon as I moved out but have yet to receive it. Here is the list of deposit-related items and early vacancy refund I am emailing you about:      $900 - Security Deposit        $900 - Last Months Rent        $250 - Pet Deposit        $225.81 - Pro-rated Rent Refund (7 days early vacancy)       Total Owed: $2,275.81 "

OF COURSE, I WOULD NEVER SAY SUCH A THING.  

My notes from the walk through inspection with Tenant show that Tenant admitted to only doing less than minimum maintenance over his 9 years of tenancy: 1. reinstalled mailbox, 2. crawled in attic once, 3. had a breaker installed (wrongly charged landlord $250 by underpaying rent on last month), 4. had small repair done on pool, which was not effective, by his own account.  

Single Page Lease from Attorney states tenant is to take care of first $200 of maintenance not including labor, monthly. Monthly rental rate set at $800 below market.

I want to claim for the approximate $10,000+ in repairs and deferred maintenance that I am paying a crew to perform, including supplies.  I am not sure the exact amounts yet and have to separate out the upgrades and normal wear and tear from what was absolutely necessary.  The entire house needed interior paint, with hundreds and hundreds of holes and kid's wall graffiti, broken cabinets, doors missing, he purposely cut off the new A/C from the rooms he didn't want to cool and that caused mold, you name it!

MY MAIN CONCERN IS HOW FAST TIME IS FLYING AND I DON'T KNOW THE FULL COSTS YET, WITH A FULL CREW WORKING EVERY DAY EXCEPT FOR BEING PULLED OFF FOR STORM EMERGENCIES HERE.  ALSO, HE DOES HAVE AN ATTORNEY INVOLVED FROM THE OTHER SIDE OF THE STATE? ODD!

I TRUST THIS FORUM AND APPRECIATE YOUR INPUT!

WHAT WOULD YOU DO?