In her heyday, my lakeland terrier despatched one or two rats most weeks for quite some time. We only saw them when she left the bodies on the lawn, never saw a live one.
She's too old for that malarkey now, and last winter one got in the house. I woke up one night to hear a hissing sound, went downstairs to investigate and found the kitchen ankle deep in water. The bloody rat had chewed through the hose to the diswasher and it was spouting water like Old Faithful.
The rat then made its way into the loft, presumably because it wanted to keep its feet dry. The council came and put down bait and traps and we never saw any evidence of it again. We blocked up a few places where mortar had come away from the pointing, and filled every tiny gap where pipes enter or leave the house.
Funnily enough though, a colleague who lives a couple of hundred yards away got them in her house a few weeks later. They got the council out, and it turned out they'd got into her house through a broken drainage pipe and she had to have half her garden dug up and new drains laid.
They're everywhere round here. We're on the edge of open countryside and have 3 lots of stables (2 racing yards and a livery stable/riding school) within half a mile, and loads of people, including my NDNs, keep chickens.