A bad tenant can cause thousands of dollars in damage and unpaid rents. 

Take any repair estimates with you to the protest such as Roof Repair, Mold damage, Foundation repairs etc , and request a Property value reduction due to the condition of the property.   

Downtown environment, 1 block off a college campus.

With that type of funding you could do some real damage in almost any CA market of your choosing.

He broke contract, and I believe TN states that I don't have to pay him back unless I find a new renter to "mitigate damages".

That gives them another 10 days to vacate but meanwhile they can do a lot of damage to my property and the sheriff is now part of the situation.If you can avoid evicting my advice is there is very little help you can get from the law, no matter where you live.

The concrete block wall would need to be filled and possibly reinforced with rebar.  

Remember if follow up inspections fail the unit the person responsible for repairing will be you even if the damage is done by the tenant.

In my area, tax sales come with an obligation to the purchaser to maintain the property and improvements, over the redemption period, and be liable to a redeeming owner for any damages.

I had to repaint and put down new flooring due to the damage they did to the house.