I had the pup from hell
Archie, who is now 22 months old was weeing indoors 20+ times a day. I used to take him outside 4/5 times an hour so you can imagine how many hours a day this was.... He'd occasionally perform outside but more often than not, come back inside (after having been out with me for 5/10 mins each time) and wee inside. I had him checked out and nothing was amiss. He used to do number 2's inside as well (sorry
) - same scenario as the wees. If I didn't work from home, I don't know how I would have handled it, although he may have clicked easier and earlier.
It took till he was 13/14 months old to become more reliable, and even now I can't let him roam free downstairs if I'm in as he's been known to do the odd wee/poo inside without asking to go out. (BTW, I still take him outside at least every hour, even at his age). It has been an incredibly frustrating and time consuming 18 months, I can tell you but the key is consistency and taking them outside regularly, using the key word and treat/praise lots afterwards.
Ironically, I can leave him alone for up to 4 hours and come back to no inside accidents - go figure