We're home to an 18 month old dog who we had from 8 weeks, toilet training came relatively easily and I felt like I had it all under control. Fast forward to now, we've recently rehomed a gorgeous 5 month old Manchester terrier (a toy one if that is relevant.) We didn't get him through a shelter, rather my OH has been working for a very wealthy man who got the MT as a ratting dog to eradicate the rats from his barn. Long story short, he needed him rehomed and said to my partner to take him as he knows how we love our dog, or else he was just going to stick him on gumtree for the first person to come along.
He doesn't have dogs as pets, they're commodities. He has two Japanese guard dogs and one of them got hold of our MT (named Beau) and he's lucky to be alive hence the need for a quick new home.
So while living there, Beau was in a crate apart from when he was needed to be in the barn or when the guard dogs were locked away so he could have a run around their garden (perhaps an acre) He never walked along the street, to a park, had cuddles etc.
He came to us, and though he was wary of our dog for a few hours (understandably) he has fitted in like a dream. He is now lavished in love and cuddles and enjoys walks in the field at the bottom of our road. It was so lovely to see him go from a dog who had no idea what it was like to be outside, to a dog who loves being out and about. Himself and Buster get on like a house of fire, all in all, we've been so lucky.
Now to the sticking point. We've had him for 4 weeks, after around 10 days, he started weeing in the house. It looks to me like he's marking as they're not large wees (then he's not a large dog) but he just cocks his leg and sprays up the wall, sofa, bin or anywhere else he fancies. He has access outside pretty much all day as it's summer(ish) so he can come in and out and I've seen him do his proper wees outside.
I just don't know how to approach this, as unlike training from a small puppy, he's not consistently weeing inside, so I'm finding it hard to catch him in the act and to correct his behaviour. I've only seen him actively do it twice and both times I said 'no' firmly and took him outside.
My OH is getting fed up of it and I really don't want him to feel like he made a mistake bringing Beau here as he's such a lovely dog.
Has anyone got any suggestions for ways to eradicate this behaviour when I don't seem to ever catch him in the act?
Picture for cuteness purposes 🐶