I got a quote for roof repair, but of course we are on a time crunch due to the contract, and as always you never know how much more damage they find when they open things up.

Hidden damages or poor construction can cause issues down the road.

However this last tenant left our unit in a very damaged and extremely filthy state that took considerable work to remedy (which was a surprise because they had been pretty responsible until this event). 

Curtain rods are damaged.

These are typically deductible in the year they’re done.On the other hand, improvements that better the property, restore it after substantial damage, or adapt it for a new use generally have to be capitalized and depreciated over time.Now, if the cost is $2,500 or less, you might be able to use the De Minimis Safe Harbor election to expense it immediately, rather than depreciating it.

Civil Suit they would need to prove damages I believe.

Property damages?

Allow showings but, you have to be careful - we do not show homes to anyone who has not provided a photo I.D. and been screened through our validation process and provided a credit card in case of damages.

Hopefully their deposit is higher than the damage, but if not, you can document everything and try small claims court, but honestly it is not worth your time as you are unlikely to see the money if you win. 

I do supply the 1" light-filtering miniblinds from Lowes (Project Source) - and yes, they get broken pretty easily, but I charge for their replacement on turnover if they are damaged, as @Kenneth Soles does.With the blinds installed, the units show better, create some opacity to thwart people trying to ascertain if the unit is vacant, and provide some privacy once the tenant moves in.