Give them 24 hours notice, go in there with a high definition video camera and get evidence of EVERYTHING. If they don't like it there is a particular universal sign language you can show them. If it is any different in a month then they have committed criminal damage in most states. They will be required to pay for this. Give them another 24 hours notice to show the house whenever you feel like it.
Additionally, I would charge an early termination fee, and they will have to continue paying rent until a new tenant can be located. These things will be SUPER easy to win in court, and it's way, way easier to collect than many who have never tried think.
And as said before, do not ever accept a security deposit as rent. If the rent is late, start with the proceedings. I would suggest you do everything you can to force replenishment of said security deposit as it is not returnable until about 30 days after they move out in undamaged condition.
Hit them with an eviction, bad credit for a judgement against them, and no kind words as a previous landlord. At least teach them a lesson, and warn the next landlord if nothing else. Would you rent to somebody with bad credit, no references, and unpaid judgements?