It might be worth a try, it is far superior to Kilz as a stain blocker. 

I'd suggest not noting things like "stabbed coach with a knife" and instead "7" long cut in left cushion of couch" and "4 sq ft area of carpet under den window coated in an unknown substance that stained the carpet". 

Hi Brian, Thank you for such a detailed response. 1. yeah his justification for only wanting bank financing does seem a little silly but he’s stubborn. 2. 

Rather than perform tests to make life more expensive these simple steps will cure most issues.Yeah, Killz can be a great solution for covering stains, especially smoke related.

If a dog damags your property IE: staining wood floors with urine the tennant is responsible for repairs. 

Otherwise, you can re-stain them with a close enough color to minimize the amount of rework.

Cabinets: is cabinet staining something you'd recommend as a DIY?

Granite is quite effective as it is scratch, stain and chip resistant.

You could always sand and stain them , a couple coats of gloss poly and you would be surprised . 

It makes the towels less absorbent and they hold onto stains much more readily.