Multi family is a little different so we have them sprayed every other month. 

.* Spray-foam attic space for cut down on heat lost; 35% of heat is lost through attic.* Install electric heat in 900 sqf 2 bedroom home.* Install supplemental Woodstove in living room.       

The roller application works better than the spray

Can he spray with minimal prep work?

We sprayed a nest that was forming, and apparently that didn’t take care of the bees.

Pepper spray comes to mind 

My first approach is to just tell the tenant to buy a wasp spray and spray it (if small), I would credit the rent that amount with an invoice (and bill to owner out of the reserve account). 

I also need someone to spray the mildewed areas under the house. 

I then sprayed two coats of mold killing, watertight primer on the walls, and a slightly different product for the ceiling.

Huge costs involved with daily spraying and DEP/Engineer monitoring.