
My friend took in a year and a half shepherd cross who lived outdoors all his life. It only took her 1 month to fully house train him and he still had his bits, never lifted in the house and would ask to go out when nature called. He loved it indoors cause he was close with a family and not left out :)
Taz was an outdoor dog till his mate passed on, he came indoors about a year ago (we would bring them both in but they would always ask to go out), he had a couple of accidents but is now doing great and loves to be indoors, he's 9 and a half years old. :)
Wish u the best :)
ttfn :)