House elves are part of a property not bound to a wizard

Yeah, Mum’s always wishing we had a house-elf to do the ironing,” said George. “But all we’ve got is a lousy old ghoul in the attic and gnomes all over the garden. House-elves come with big old manors and castles and places like that; you wouldn’t catch one in our house

“You see,” Dumbledore said, turning back to Harry and again speaking as though Uncle Vernon had not uttered, “if you have indeed inherited the house, you have also inherited —” He flicked his wand for a fifth time. There was a loud crack, and a house-elf appeared, with a snout for a nose, giant bat’s ears, and enormous bloodshot eyes, crouching on the Dursleys’ shag carpet and covered in grimy rags. Aunt Petunia let out a hair-raising shriek; nothing this filthy had entered her house in living memory. Dudley drew his large, bare, pink feet off the floor and sat with them raised almost above his head, as though he thought the creature might run up his pajama trousers, and Uncle Vernon bellowed, “What the hell is that?” “Kreacher,” finished Dumbledore.