@Theodore Rivera what you need is a post nuptial agreement.

(the odors being my biggest concern!!)

It's expensive.In my case, we had to remove the carpet, the padding, and then tried the odor remover, which didn't work sufficiently.

Those carpets and pads must be pulled and the odors removed before new pads and carpets go in.And no Virginia, pet deposits will not take care of this, they can contribute but these people should talk first before the landlord does his checkout and try to come to some agreement to ease his pain and in turn theirs.Talk first, do not make them chase you or any chances of a reasonable settlement go out the window, or they would for me.

I imagine some of those products mentioned on another thread some time ago would help to clean the living space and yard, but I wonder if they would eliminate all the odors.

Poorly house trained dogs can also create the necessity to replace all carpets and pads to remove the odor.

Use the "search" feature on BP.Depending on how extensive the odor is, you may need a multilayered approach.When we rehabbed a house that previous owners lived in and smoked in for decades, we found that we had to go much deeper than walls and paint. 

He has a severe cockroach infestation that has migrated over to my property along with the odors.

@James WiseI don’t know, there are times if the home stays nasty for so long that the odors will start getting into the walls.

@Theodor Morgan, buying a multi-family is a very common (and effective) strategy that many new homeowners/investors have employed.Run the property through the BP Calculators to find out how good a deal it is.