Ortho Home Defense works consistently for me. I spray the exterior, not the interior. I spray the openings, any thing that touches the ground (face and all sides of tires, hoses, cables), bottom side all around the sides of the RV (as far as the spray can go), around windows and door openings, around the vents (I also have those screened). I have a solar bug light that sits a ways off from the entrance door and that helps keep the flying bugs down. I do this about twice a year (spring and fall) plus sometimes I will repeat if there has been a heavy rain (currently in NM where it rarely has heavy rains). I also spray a bit around the ground near the tires. I spray the outside carpet (top side and the ground under) as the roaches seem to like to have parties and family reunions under it. I have a large box I carry on a hitch haul that I set on the ground sometimes as it makes a nice bench. I spray under that as well as empty it out twice a year and spray the interior (repack when it's dry). I have not had a bug problem since I started using the Ortho Home Defense. I also spray the interior of my towed as well. Some places in NM have lots of roaches. Ick!