Cost to cure lingo or a plain new bid.What techniques have you used when dealing with this?

This is pure capitalism. the lienholder, ultimately, really justs wants a 'cure' for the default and a resolution.

Or a whole house filter for a while and see if improvement is noted.Pex pipe if allowed by your code,,,is so cheap and easy to do,,,and cures a multitude of problems.I used to have a house with similar to your problems. 

Also, any charges from the locksmith will be added to the rent due for the nest month.If not, then a cure or quit notice and proceed to evict.

she should have the ability the cure the default (at closing) and you help her restore her credit by keeping a positive tradeline on the books. 

Did the tenant give notice of the nuisance and allow you to cure it?

If a problem is discovered during the title search, the foreclosure Attorney will have to cure it.

Could I include that in a 10 day with cure notice, for instance?

The craftsmen places the mix and at the cure time you polish it with a flex wheel.

At that point I'd either eat my EMD and chalk it up as a paid education and/or pray for a title defect that can't be cured anytime soon...