This makes the whole house seem really trashy and thus borderline unrentable.The carpet needs to be replaced and I need to do something about that smell before I can show it to potential tenants.

If there is dog urine, don't be surprised if it seeped through the carpeting, to the carpet pad, or even to the floor underneath.

Currently the two main stairwells are carpeted and the back stairwell is linoleum.The building was built as two separate buildings over the years.

Big negative for the house is that the current owner, a retired gentleman who is a smoker, has therefore made it smell like an ash tray (was painted in the last few years, so no terrible stains) and therefore will get rid of carpet and replace with laminate, and seal and paint throughout.

I have an offer in on a house that has pretty bad stains on the carpets.  

Two dogs over 60 lbs, and it's just when you walk in at the end of the day and there's been no air moving around when you get that"musty" odor and there isn't a specific location it's coming from.We vacuum regularly, cleaned the carpets recently, bought a $350 air purifier, mop/dust, etc - it's still there.  

Scope of work:Rip up carpet and tile and disposeLay snap-in floorsChange vanity and wall mirrors in bathroomsRemove an above ground poolRepair and replace a few windowsAdd and change a few doorsPlease let me know if you recommend anyone.

It needs cosmetic updates such as carpet, paint and granite in kitchen.

Maybe a little new carpet and low end kitchen appliances, and it should be good to go.

The company will most likely advice you to strip the walls of paint and remove all carpet flooring.