Already do most of the stuff in there. I never tried baiting the area first without a set trap. But I do set the traps along/near walls. I saw dust debris in basement between wall and first floor that was probably them. I check the that outside wall and see what I find.
Once when I was trying to take a nap. I heard a spoon moving on a table nearby. When I looked there was a mouse brazenly licking the spoon in a cereal bowl I had sitting on the table. I had four cats sleeping on various pieces of furniture in the room and none of the woke up to see what the noise was. I took a towel from the kitchen, grabbed the mouse and put it outside. Lousy cats.
Duct tape your table legs with the sticky side facing out or spray some furniture polish on them to make them slick. Set your traps parallel with your walls touching the walls because they travel along walls.
They can climb anywhere they want. I moved out of a house in the country where I never won my war with them. And yes, I killed them and never felt bad. I had 4 cats and a dog that would get them daily, but I always had more. I counted 17 killed in a couple of months from my pantry alone. They did not get into any food because I had it all protected. They would get into a cupboard I had and leave their calling card on my dishes. And if you have a gas oven, don't store your pans in there because they will get in there when it is cold. I had to set traps on top of my stove every night and sterilize it the next morning.