I dont know if I want to try Kilz, or just rip out the hardwoods and any subfloor and start over.

I know these are not the usual materials used for a flip but I cringe when I am putting hard wood floors instead of doing something more exciting such as doing epoxy floors. 

To which the landlord replied:"Please understand that it is impossible to fix damaged floorboards in small spots on a hardwood floor without tearing up the boards and then sanding the floor and restaining the room.

I'm sure the old owners had tons of cats even prior to that.Were you spraying on hardwood for your house or some other material?

High end neighborhood so Hardwood throughout except bedrooms.

You're most sure bet is to buy a site built 3bed/2bed 1400sq foot plus house that needs a major repair like a new roof but otherwise is in good shape with hardwood floors.

Real hardwood?

Only a refer and stove  .. no garborator no dishwasher no laundery.so at tenant turn over it was high pressure hose and wash it all out.. genius really.most of my guys in the lower end stuff  have older homes that have hard woods under the carpet they rip carpet out and just paint the hard wood.. some will stain.. those are much easier to care for they have character when you have flaws in them.others I know that have carpet instead of replacing they just dye them a darker color to match the stains. until the carpet ends up very dark brown.. you simply can't compare your SF  high rentals to rentals in other markets you know that you wen through it in PHX..  

Paint, spackle, make ready clean, maybe some restaining or refinishing of warn spots on the hardwoods etc. 

In the kitchen and the front entry, there is old-style oak hardwood, about 2 inches wide and probably 3/4 of an inch thick.