They will have weeds grow in between the cracks eventually which looks terrible and more work spraying and pulling weeds for the landscaper.  

For $2000, I can buy ten vinyl replacement windows that size and have a hundred bucks left over for silicone caulk and spray foam.

Really weeds in paves, SPRAY ROUNDUP! 

Next step is waterproofing the foundation (spraying a tar-like substance on the concrete and laying a foundation drain around the perimeter of the structure), and then it's on to framing.

I'm looking for somebody who can spray out an entire apartment.  

This pest issues is a big expense and really hard to control if tenant does not comply with complete instructions for handling their furniture and personal belongings and electronics during treatment.Pest addendum is great for pest control services and responsibility but like you said it's hard to be judge as to how the pest was introduced.. at this point you need to service and control issue for your property investment.Any furniture / mattresses put out side for disposal mark with spray paint BED BUGS so it's not transferred back into the building.. 

So when you are fogging and spraying and Etcetera, they might be just down in their little fallout shelter, Waiting for the air to clear up.

-Bedbug treatment -Family pack of Roach spray -Mace -Bullet proof vest -Big Bottle of mad dog booze to celebrate after you get your first months rent ! 

We even use scented room sprays before showings so that ALL the buyers senses are attacked as they go through.

FYI, I've been pepper sprayed in the face when I was in the military.