Dip the tank when the tenant moves in , measure the inches in the tank , you can find a chart online that converts the inches to gallons .

Were precise figures obtained for the condition capex?

I have had applicants with actual scores so low they did not register on the chart.

So really it wouldn't hurt to try.This was going to be my suggestion precisely but I will add a couple items.  1) As others have stated the chance of getting any of the money owed is low 2). 

Must be the news media...or some chart that gives the average numbers. 

You are taking offense that someone has suggested you contact an attorney, but this is precisely what you need to do, and do it now.

there is a very precise way it needs to be calculated using the useful life left of the damaged item to calculate the amount you can withhold for example if carpet was damaged and the useful life of the carpet was 5 years and the carpet is 5 years old you cant charge them at all    To answer your question I would create a deposit accounting and describe in detail what you are charging for .  

The entire peninsula, from the City to San Jose has gone off the charts, not sure the level of upside remaining, especially in comparison to other areas.

Actually, by answering the following, you will know what to do and be able to chart a course of positive action.

I tell them I don't want anyone living in my properties that doesn't want to be there, and that is precisely what would happen if they signed a year lease and their situation changed.