You need to think like a rat.
what does a rat primarily want? Food, water, shelter, mate.
look at your situation, what rat needs might you or your neighbors be accommodating?
you can likely impact 2 or 3!of those and make the area less hospitable to the rat.
Gold help you if you are your neighbors are assisting with the mating need. I’d move.
Could be you are helping with shelter. Can you find where your rat is sleeping during the day? Holes in the wall? Check your base boards for fecal trails. Rats hate open spaces so he/she is probably slinking along a wall to feel protected on one of his flanks. Do you have a bunch of stuff along the garage wall creating a safe space for him to travel along? Wall on one flank and boxes on the other creating a cozy little path for him/her to travel to his/her destination? Is so move the stuff off the walls to make his/her path feel more dangerous and less hospitable.
find the nest. When we bought the house we are in, in the first two weeks after moving in I came face to face with a rat in the garage sitting on the hot water heater. I chunked the can of seltzer water I had come for at him. Of course I missed. But that is when I found the hole where the pipes come out if the wall. Ok how did he get in that hole?
Next day, Check garage base boards, no droppings. No droppings on baseboard all the way to the garage door and oh look steel wool (they hate steel wool) jammed between the garage door track and the wall. So previous owner must have encountered this rat and didn’t bother to mention that. Keep going with visual inspection of exterior.
let’s look behind this shrub that aligns with the hot water heater. Oh what’s this unusually place pile of stone pavers next to the foundation? Oh it’s attempting to cover this hole in the siding that lines up with the hot water heater.
new exterior siding panel installed , go to the hot water heater hole, 3 cans of foam, and for good measure dump some poison in the hole before finishing off with more foam seal.
on to food. No food other than canned drinks in garage and a freezer. If he/she can open the freezer door, they win I give up. Start looking at neighbor yard. Lady next door has a bird bath and bird feeder. Strike up casual conversation with her mention I saw a rat has she. Why actually she has. Mention food water shelter concept. She says I bet they are coming to my bird bath and bird feeder. She drains the bath and starts taking the feeder down at dusk. Good neighbor!
Talk to other neighbor, mention rats, food water, shelter. Seen rats on fence, blames it on creek a quarter mile away. Couldn’t have anything to do with his ramshackle shed in backyard or brush piles he never disposed of. Oh well not much I can do here.
see occasional rat using back fence as a rodent super highway. Rabbits use the bottom of the fence, rats on the middle stringer and squirrels and possum traffics on the top stringer.
but no more rats in garage.