The premixed acrylic grouts that MUST be used with them are self sealing in 24 hours and very stain resistant.

The best color by far is NO stain color.

You just want to make sure not wasting a trip + time + gas to look at a home with a ridiculous price and stubborn seller.

For the attic I am looking a at the sheathing underneath if there is insulation I am looking and feeling for damp or water stains.

I still need to play with the camera settings and go back for more photos, but, you can see below a reminder of why we have a No Pet policy:This is what many years of "doggie diapers" at the end of the hallway look like ... yes, the yellowish and brown areas are urine stains.  

I would decline to do any cleaning  Yes, the tenant may have stained the carpet already and is preemptively trying to get out of a future damage charge.

Tile, wood-look waterproof vinyl planks, stain concrete, etc. will be your best friends.

I believe I cleaned all living spaces as well as one could, minus normal wear (nail/tack holes in walls, nicks, light staining etc).- I cleaned kitchen and bathroom NOT QUITE AS THOROUGHLY AS I WOULD'VE LIKED.

I realized I was slowly whittling away at her stubborn W-2 working ways because she was fine with me getting a realtor. 

@Ryan SwanLuxury vinyl plank has become quite popular in recent years due to its resistance to water and staining.