They do not sand floors they clean, cover flaws and stain and varnish.  

Make the grout a dark color so that you wont see any stains on the grout as the years go by.

When a Tenant comes back to me and tells me there's a crack in the ceiling, or they don't like the stain in the bedroom carpet, I point them to this lease and leave it at that.Your obligation as a Landlord is to ensure everything is safe and functional.

The previous owner smoked for 15 years in the property so I kilzed everything to remove the stains and smell.

We got a new septic system and new roof out of the deal due to lack of maintenance and staining on the roof.

Had spills, stains, and what should have been scratches.

The floor should have been sanded down, re-stained and then put 2 to 3 coats of polyurethane.

Our clients tend to have bad experience with hard water/mineral stains in the bathrooms we renovate, so we've made it a practice to deal with the additional cost and minor headaches of epoxy grout for all client work, as it improves customer satisfaction, and helps reduce the number of service calls for return work.

They may surprise you and tell you that they realize the dog tore up the carpet and it has to be replaced.If they don't admit any fault by their dog, you can ask them what they think is fair and send them the pictures of the torn carpet and then maybe you can find a middle ground with them.I just went through a similar situation with my tenants when they moved out (huge red wine stain and water damage from a utility sink that overflowed because they left some clothes in there to soak).  

Personally, I would stain the deck over painting.